diff --git a/src-tauri/src/proxy/handlers/gemini.rs b/src-tauri/src/proxy/handlers/gemini.rs
index 9fa2c2a33..6c80d474d 100644
--- a/src-tauri/src/proxy/handlers/gemini.rs
+++ b/src-tauri/src/proxy/handlers/gemini.rs
@@ -343,7 +343,9 @@ pub async fn handle_generate(
                             Some(Ok(b)) => b,
                             Some(Err(e)) => {
                                 error!("[Gemini-SSE] Connection error: {}", e);
-                                yield Err(format!("Stream error: {}", e));
+                                // Yield error as SSE content to prevent hyper aborting chunked encoding (TransferEncodingError)
+                                let error_msg = format!("{}", e).replace('"', "'");
+                                yield Ok(Bytes::from(format!("data: {{\"error\":{{\"message\":\"{}\",\"type\":\"stream_error\"}}}}\n\n", error_msg)));
                                 break;
                             }
                             None => break,
diff --git a/src-tauri/src/proxy/mappers/claude/mod.rs b/src-tauri/src/proxy/mappers/claude/mod.rs
index 9ae853006..a59cc438b 100644
--- a/src-tauri/src/proxy/mappers/claude/mod.rs
+++ b/src-tauri/src/proxy/mappers/claude/mod.rs
@@ -82,7 +82,9 @@ where
                             }
                         }
                         Err(e) => {
-                            yield Err(format!("Stream error: {}", e));
+                            // Yield error as SSE content to prevent hyper aborting chunked encoding (TransferEncodingError)
+                            let error_msg = format!("{}", e).replace('"', "'");
+                            yield Ok(Bytes::from(format!("event: error\ndata: {{\"error\":{{\"message\":\"{}\",\"type\":\"stream_error\"}}}}\n\n", error_msg)));
                             break;
                         }
                     }