diff --git a/src/main/resources/templates/notifications/compose.html b/src/main/resources/templates/notifications/compose.html
index 0a87858..f35cad8 100644
--- a/src/main/resources/templates/notifications/compose.html
+++ b/src/main/resources/templates/notifications/compose.html
@@ -5,7 +5,7 @@
     <div class="d-flex flex-wrap justify-content-between align-items-center gap-3 mb-4">
         <div>
             <h1 class="h3 mb-1 fw-semibold">대상 공지 발송</h1>
-            <p class="text-muted-soft mb-0">닉네임으로 사용자를 선택해 관리자 메시지를 푸시 및 인앱 알림으로 발송합니다.</p>
+            <p class="text-muted-soft mb-0">ID 또는 닉네임으로 사용자를 선택해 관리자 메시지를 푸시 및 인앱 알림으로 발송합니다.</p>
         </div>
         <a th:href="@{/notices}" class="btn btn-outline-secondary d-inline-flex align-items-center gap-1">
             <i class="bi bi-megaphone"></i>
@@ -32,11 +32,11 @@ <h1 class="h3 mb-1 fw-semibold">대상 공지 발송</h1>
                     <form id="notificationSendForm" class="row g-4" method="post" th:action="@{/notifications/send}"
                           autocomplete="off" onsubmit="return confirm('입력한 대상에게 공지를 발송할까요?');">
                         <div class="col-12">
-                            <label class="form-label fw-semibold" for="recipientSearch">수신자 닉네임</label>
+                            <label class="form-label fw-semibold" for="recipientSearch">수신자 검색</label>
                             <input id="notificationUserIds" name="userIds" type="hidden" th:value="${form.userIdsRaw}">
                             <div class="position-relative">
                                 <input id="recipientSearch" type="search" class="form-control form-control-lg"
-                                       placeholder="닉네임을 입력해 검색하세요"
+                                       placeholder="ID 또는 닉네임 입력 (여러 ID는 콤마/공백으로 구분)"
                                        autocomplete="off"
                                        th:disabled="${!canSend}">
                                 <div id="recipientSuggestions"
@@ -45,7 +45,8 @@ <h1 class="h3 mb-1 fw-semibold">대상 공지 발송</h1>
                             </div>
                             <div id="selectedRecipients" class="d-flex flex-wrap gap-2 mt-3"></div>
                             <div class="form-text">
-                                닉네임 검색 결과에서 사용자를 선택하세요. 중복 선택은 자동으로 제외됩니다.
+                                닉네임으로 검색해 결과를 클릭하거나, ID(숫자)를 직접 입력해 추가할 수 있습니다.
+                                콤마/공백으로 구분해 여러 ID를 한 번에 추가하거나 Enter로 첫 번째 항목을 선택하세요.
                             </div>
                         </div>
 
@@ -159,12 +160,42 @@ <h2 class="h6 fw-semibold mb-3">미리보기</h2>
                 if (!user) {
                     return '';
                 }
-                if (user.nickname && user.nickname.charAt(0) === '#') {
+                if (!user.nickname) {
+                    return '#' + user.id;
+                }
+                if (user.nickname.charAt(0) === '#') {
                     return user.nickname;
                 }
                 return user.nickname + ' (#' + user.id + ')';
             }
 
+            function parseNumericTokens(raw) {
+                if (!raw) {
+                    return null;
+                }
+                var tokens = raw.trim().split(/[,\s]+/).filter(Boolean);
+                if (tokens.length === 0) {
+                    return null;
+                }
+                var seen = {};
+                var ids = [];
+                for (var i = 0; i < tokens.length; i++) {
+                    if (!/^\d+$/.test(tokens[i])) {
+                        return null;
+                    }
+                    var n = parseInt(tokens[i], 10);
+                    if (!(n > 0)) {
+                        return null;
+                    }
+                    var idStr = String(n);
+                    if (!seen[idStr]) {
+                        seen[idStr] = true;
+                        ids.push(idStr);
+                    }
+                }
+                return ids;
+            }
+
             function syncSelectedRecipients() {
                 if (userIdsEl) {
                     userIdsEl.value = selectedUsers.map(function (user) {
@@ -243,7 +274,71 @@ <h2 class="h6 fw-semibold mb-3">미리보기</h2>
                 syncPreview();
             }
 
-            function renderSuggestions(users) {
+            function addRecipientsByIds(ids) {
+                ids.forEach(function (rawId) {
+                    var id = String(rawId);
+                    var exists = selectedUsers.some(function (selected) {
+                        return selected.id === id;
+                    });
+                    if (!exists) {
+                        selectedUsers.push({ id: id, nickname: '#' + id });
+                    }
+                });
+                if (searchEl) {
+                    searchEl.value = '';
+                    searchEl.focus();
+                }
+                hideSuggestions();
+                syncSelectedRecipients();
+                syncPreview();
+            }
+
+            function buildSuggestionButton(leftText, rightText, onClick) {
+                var button = document.createElement('button');
+                button.type = 'button';
+                button.className = 'list-group-item list-group-item-action d-flex justify-content-between align-items-center';
+                var leftSpan = document.createElement('span');
+                leftSpan.textContent = leftText;
+                var rightSpan = document.createElement('span');
+                rightSpan.className = 'text-muted small';
+                rightSpan.textContent = rightText;
+                button.appendChild(leftSpan);
+                button.appendChild(rightSpan);
+                button.addEventListener('click', onClick);
+                return button;
+            }
+
+            function renderBulkIdSuggestions(ids) {
+                if (!suggestionsEl) {
+                    return;
+                }
+                suggestionsEl.innerHTML = '';
+                var unselected = ids.filter(function (id) {
+                    return !selectedUsers.some(function (selected) {
+                        return selected.id === id;
+                    });
+                });
+                if (unselected.length === 0) {
+                    showSuggestionMessage('입력한 ID가 모두 이미 추가되어 있습니다.');
+                    return;
+                }
+                var preview = unselected.slice(0, 5).map(function (id) {
+                    return '#' + id;
+                }).join(', ');
+                if (unselected.length > 5) {
+                    preview += ' 외 ' + (unselected.length - 5) + '개';
+                }
+                suggestionsEl.appendChild(buildSuggestionButton(
+                        unselected.length + '개 ID 일괄 추가',
+                        preview,
+                        function () {
+                            addRecipientsByIds(unselected);
+                        }
+                ));
+                suggestionsEl.classList.remove('d-none');
+            }
+
+            function renderSuggestions(users, directAddId) {
                 if (!suggestionsEl) {
                     return;
                 }
@@ -253,22 +348,32 @@ <h2 class="h6 fw-semibold mb-3">미리보기</h2>
                         return selected.id === String(user.id);
                     });
                 });
-                if (candidates.length === 0) {
-                    showSuggestionMessage('검색 결과가 없습니다.');
-                    return;
+                var needsDirectAdd = directAddId
+                        && !selectedUsers.some(function (s) { return s.id === directAddId; })
+                        && !candidates.some(function (u) { return String(u.id) === directAddId; });
+                if (needsDirectAdd) {
+                    suggestionsEl.appendChild(buildSuggestionButton(
+                            'ID 그대로 추가',
+                            '#' + directAddId,
+                            function () {
+                                addRecipientsByIds([directAddId]);
+                            }
+                    ));
                 }
                 candidates.forEach(function (user) {
-                    var button = document.createElement('button');
-                    button.type = 'button';
-                    button.className = 'list-group-item list-group-item-action d-flex justify-content-between align-items-center';
-                    button.innerHTML = '<span></span><span class="text-muted small"></span>';
-                    button.querySelector('span:first-child').textContent = user.nickname;
-                    button.querySelector('span:last-child').textContent = '#' + user.id;
-                    button.addEventListener('click', function () {
-                        addRecipient(user);
-                    });
-                    suggestionsEl.appendChild(button);
+                    var label = user.nickname || '(닉네임 없음)';
+                    suggestionsEl.appendChild(buildSuggestionButton(
+                            label,
+                            '#' + user.id,
+                            function () {
+                                addRecipient(user);
+                            }
+                    ));
                 });
+                if (!suggestionsEl.firstChild) {
+                    showSuggestionMessage('검색 결과가 없습니다.');
+                    return;
+                }
                 suggestionsEl.classList.remove('d-none');
             }
 
@@ -278,6 +383,13 @@ <h2 class="h6 fw-semibold mb-3">미리보기</h2>
                     hideSuggestions();
                     return;
                 }
+                var numericIds = parseNumericTokens(trimmed);
+                if (numericIds && numericIds.length > 1) {
+                    latestSearchSeq++;
+                    renderBulkIdSuggestions(numericIds);
+                    return;
+                }
+                var directAddId = numericIds && numericIds.length === 1 ? numericIds[0] : null;
                 var searchSeq = ++latestSearchSeq;
                 fetch('/notifications/users/search?q=' + encodeURIComponent(trimmed), {
                     headers: {
@@ -295,10 +407,15 @@ <h2 class="h6 fw-semibold mb-3">미리보기</h2>
                             if (searchSeq !== latestSearchSeq) {
                                 return;
                             }
-                            renderSuggestions(data && data.users ? data.users : []);
+                            renderSuggestions(data && data.users ? data.users : [], directAddId);
                         })
                         .catch(function () {
-                            if (searchSeq === latestSearchSeq) {
+                            if (searchSeq !== latestSearchSeq) {
+                                return;
+                            }
+                            if (directAddId) {
+                                renderSuggestions([], directAddId);
+                            } else {
                                 showSuggestionMessage('사용자 검색에 실패했습니다.');
                             }
                         });
@@ -345,6 +462,20 @@ <h2 class="h6 fw-semibold mb-3">미리보기</h2>
                 searchEl.addEventListener('keydown', function (event) {
                     if (event.key === 'Escape') {
                         hideSuggestions();
+                        return;
+                    }
+                    if (event.key === 'Enter') {
+                        if (suggestionsEl && !suggestionsEl.classList.contains('d-none')) {
+                            var firstAction = suggestionsEl.querySelector('button.list-group-item-action');
+                            if (firstAction) {
+                                event.preventDefault();
+                                firstAction.click();
+                                return;
+                            }
+                        }
+                        if (searchEl.value.trim()) {
+                            event.preventDefault();
+                        }
                     }
                 });
             }
diff --git a/src/main/resources/templates/users/list.html b/src/main/resources/templates/users/list.html
index a0ef221..5cd63e2 100644
--- a/src/main/resources/templates/users/list.html
+++ b/src/main/resources/templates/users/list.html
@@ -5,7 +5,7 @@
     <div class="d-flex flex-wrap justify-content-between align-items-center gap-3 mb-4">
         <div>
             <h1 class="h3 mb-1 fw-semibold">사용자 목록</h1>
-            <p class="text-muted-soft mb-0">대상 공지 발송에 사용할 사용자 ID와 닉네임을 조회합니다.</p>
+            <p class="text-muted-soft mb-0">ID 또는 닉네임으로 사용자를 조회합니다.</p>
         </div>
     </div>
 
@@ -18,9 +18,9 @@ <h1 class="h3 mb-1 fw-semibold">사용자 목록</h1>
         <div class="card-body card-body-comfy">
             <form class="row g-3 align-items-end" method="get">
                 <div class="col-md-5">
-                    <label class="form-label small text-uppercase text-muted" for="userQuery">닉네임 검색</label>
+                    <label class="form-label small text-uppercase text-muted" for="userQuery">ID/닉네임 검색</label>
                     <input type="search" class="form-control" id="userQuery" name="q"
-                           placeholder="닉네임 일부를 입력하세요" th:value="${query}"
+                           placeholder="ID 또는 닉네임 일부를 입력하세요" th:value="${query}"
                            th:disabled="${!canViewUsers}">
                 </div>
                 <div class="col-md-2">
@@ -53,7 +53,12 @@ <h1 class="h3 mb-1 fw-semibold">사용자 목록</h1>
                 </tr>
                 <tr th:each="user : ${users}">
                     <td class="fw-semibold" th:text="${'#' + user.id()}">#501</td>
-                    <td th:text="${user.nickname()}">솔바람</td>
+                    <td>
+                        <span th:if="${user.nickname() != null and !#strings.isEmpty(user.nickname())}"
+                              th:text="${user.nickname()}">솔바람</span>
+                        <span th:unless="${user.nickname() != null and !#strings.isEmpty(user.nickname())}"
+                              class="text-muted small">(닉네임 없음)</span>
+                    </td>
                 </tr>
                 </tbody>
             </table>