diff --git a/README.md b/README.md
index e28da9b..00c2935 100644
--- a/README.md
+++ b/README.md
@@ -59,7 +59,8 @@ Run
   --host 127.0.0.1 \
   --port 8080 \
   --worker 4 \
-  --timeout-ms 2000
+  --timeout-ms 2000 \
+  --max-header-size 8192
 ```
 
 This command starts a server listening on `127.0.0.1:8080` with 4 preforked worker processes and a 2‑second accept timeout.
@@ -83,4 +84,3 @@ Tests cover:
 - URL parsing (`http/http.rs`)
 - Echo server logic (`process/echo.rs`)
 - Worker manager integration (`worker/manager.rs`)
-
diff --git a/src/args.rs b/src/args.rs
index 57bc4ff..319ad24 100644
--- a/src/args.rs
+++ b/src/args.rs
@@ -13,4 +13,6 @@ pub struct Args {
     pub worker: u32,
     #[arg(short, long, default_value_t = 500)]
     pub timeout_ms: u64,
+    #[arg(long, default_value_t = 8196)]
+    pub max_header_size: usize,
 }
diff --git a/src/http/http.rs b/src/http/http.rs
index 2c78d22..dbdcbf8 100644
--- a/src/http/http.rs
+++ b/src/http/http.rs
@@ -1,7 +1,7 @@
 use std::{
     collections::HashMap,
     io::{BufRead, BufReader, Write},
-    net::TcpStream,
+    net::{SocketAddr, TcpStream},
     time::{Duration, SystemTime},
 };
 
@@ -17,6 +17,7 @@ use crate::{
 };
 
 pub struct Http1<T: Handler> {
+    max_header_length: usize,
     handler: T,
 }
 
@@ -36,9 +37,14 @@ where
         log::trace!("Write timeout: {:?}", stream.write_timeout());
 
         let mut reader = BufReader::new(&stream);
-        let header_res: Result<(usize, Vec<String>), Error> = self.read_header(&mut reader);
+        let header_res: Result<(usize, Vec<String>), Error> =
+            self.read_header(client_addr, &mut reader);
         if let Err(err) = header_res {
-            return Err(process::Error::IoFail(format!("Read header failed: ({})", err)));
+            self.error_response_for_invalid_request(&stream);
+            return Err(process::Error::IoFail(format!(
+                "Read header failed: ({})",
+                err
+            )));
         }
 
         let (header_readed, headers) = header_res.unwrap();
@@ -46,15 +52,7 @@ where
         let res_request: Result<HttpRequest<'_>, Error> =
             self.init_request(client_addr, &headers, reader);
         if let Err(err) = res_request {
-            let mut response = HttpResponse::new(HttpVersion::default(), &stream);
-
-            response.set_response_code(HttpResponseCode::BadRequest);
-            response.set_header(&server(HttpHeaderValue::Str("server_rs")));
-            response.set_header(&content_type(HttpHeaderValue::Str("text/plain")));
-            response.set_header(&date(SystemTime::now()));
-            let _ = response.write("Invalid request".as_bytes());
-            let _ = response.flush();
-
+            self.error_response_for_invalid_request(&stream);
             return Err(process::Error::ParseFail(err.to_string()));
         }
 
@@ -81,12 +79,16 @@ impl<T> Http1<T>
 where
     T: Handler,
 {
-    pub fn new(handler: T) -> Self {
-        return Http1 { handler };
+    pub fn new(max_header_length: usize, handler: T) -> Self {
+        return Http1 {
+            max_header_length,
+            handler,
+        };
     }
 
     fn read_header<'a>(
         &self,
+        client_addr: &SocketAddr,
         reader: &mut BufReader<&'a TcpStream>,
     ) -> Result<(usize, Vec<String>), Error> {
         let mut res = vec![];
@@ -99,6 +101,13 @@ where
             }
             readed += result.unwrap();
 
+            if readed > self.max_header_length {
+                return Err(Error::BadRequest(
+                    client_addr.clone(),
+                    "header size limit exceed",
+                ));
+            }
+
             while buf
                 .chars()
                 .nth(0)
@@ -185,6 +194,17 @@ where
 
         return header_map;
     }
+
+    fn error_response_for_invalid_request(&self, stream: &TcpStream) {
+        let mut response = HttpResponse::new(HttpVersion::default(), stream);
+
+        response.set_response_code(HttpResponseCode::BadRequest);
+        response.set_header(&server(HttpHeaderValue::Str("server_rs")));
+        response.set_header(&content_type(HttpHeaderValue::Str("text/plain")));
+        response.set_header(&date(SystemTime::now()));
+        let _ = response.write("Invalid request".as_bytes());
+        let _ = response.flush();
+    }
 }
 
 fn parse_url(query: &str) -> (String, HashMap<&str, Vec<&str>>) {
diff --git a/src/http/value.rs b/src/http/value.rs
index f35db92..6f7fe43 100644
--- a/src/http/value.rs
+++ b/src/http/value.rs
@@ -1,4 +1,4 @@
-use std::{fmt::Display, hash::Hash};
+use std::{fmt::Display, hash::Hash, net::SocketAddr};
 
 pub enum HttpVersion {
     Http10,
@@ -139,10 +139,10 @@ impl HttpResponseCode {
 #[allow(dead_code)]
 #[derive(Debug, Clone)]
 pub enum Error {
-    #[allow(dead_code)]
     ParseFail(String),
     ReadFail(String),
     WriteFail(String),
+    BadRequest(SocketAddr, &'static str),
 }
 
 impl std::fmt::Display for Error {
@@ -151,6 +151,7 @@ impl std::fmt::Display for Error {
             Error::ParseFail(m) => ("parse fail", m),
             Error::ReadFail(m) => ("read fail", m),
             Error::WriteFail(m) => ("write fail", m),
+            Error::BadRequest(remote, msg) => ("bad request", &format!("{} {}", remote, msg)),
         };
 
         return f.write_fmt(format_args!("HttpError: [{}] {}", name.0, name.1));
diff --git a/src/main.rs b/src/main.rs
index f1829f3..bfd4374 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -69,7 +69,7 @@ fn main() {
         host: arg.host.clone(),
         port: arg.port,
         worker: arg.worker,
-        process: Rc::new(Http1::new(SimpleHandler)),
+        process: Rc::new(Http1::new(arg.max_header_size, SimpleHandler)),
     }];
 
     let mut server = Server::new(ServerArgs {