diff --git a/crates/shadowsocks-service/src/local/dns/upstream.rs b/crates/shadowsocks-service/src/local/dns/upstream.rs
index db4237b9729c..9500e4db45a9 100644
--- a/crates/shadowsocks-service/src/local/dns/upstream.rs
+++ b/crates/shadowsocks-service/src/local/dns/upstream.rs
@@ -149,7 +149,7 @@ impl DnsClient {
                 let bytes = msg.to_vec()?;
                 socket.send(&bytes).await?;
 
-                let mut recv_buf = [0u8; 256];
+                let mut recv_buf = [0u8; 512];
                 let n = socket.recv(&mut recv_buf).await?;
 
                 Message::from_vec(&recv_buf[..n])
@@ -171,7 +171,7 @@ impl DnsClient {
                 let bytes = msg.to_vec()?;
                 socket.send_with_ctrl(ns, control, &bytes).await?;
 
-                let mut recv_buf = [0u8; 256];
+                let mut recv_buf = [0u8; 512];
                 let (n, _, recv_control) = socket.recv_with_ctrl(&mut recv_buf).await?;
 
                 if let Some(server_control) = recv_control {