diff --git a/prefix_writer.go b/prefix_writer.go
new file mode 100644
index 0000000..2be05ad
--- /dev/null
+++ b/prefix_writer.go
@@ -0,0 +1,52 @@
+package gobridge
+
+import (
+	"bytes"
+	"io"
+	"sync"
+)
+
+// prefixWriter 对每一行输出添加固定前缀，线程安全。
+type prefixWriter struct {
+	mu     sync.Mutex
+	w      io.Writer
+	prefix []byte
+	buf    []byte
+}
+
+func newPrefixWriter(w io.Writer, prefix string) *prefixWriter {
+	return &prefixWriter{w: w, prefix: []byte(prefix)}
+}
+
+func (p *prefixWriter) Write(b []byte) (int, error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	n := len(b)
+	p.buf = append(p.buf, b...)
+
+	for {
+		idx := bytes.IndexByte(p.buf, '\n')
+		if idx < 0 {
+			break
+		}
+		line := append(p.prefix, p.buf[:idx+1]...)
+		if _, err := p.w.Write(line); err != nil {
+			return n, err
+		}
+		p.buf = p.buf[idx+1:]
+	}
+	return n, nil
+}
+
+// flush 将缓冲区中尚未以换行结尾的内容输出（进程退出时调用）。
+func (p *prefixWriter) flush() {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if len(p.buf) > 0 {
+		line := append(p.prefix, p.buf...)
+		line = append(line, '\n')
+		p.w.Write(line) //nolint
+		p.buf = nil
+	}
+}
diff --git a/worker.go b/worker.go
index 4e1a5cd..5ed5477 100644
--- a/worker.go
+++ b/worker.go
@@ -60,18 +60,20 @@ func (w *worker) start() error {
 		fmt.Sprintf("GOBRIDGE_WORKER_ID=%d", w.id),
 		fmt.Sprintf("GOBRIDGE_WORKER_COUNT=%d", w.cfg.workers),
 		"GOBRIDGE_DEATH_FD=3", // ExtraFiles[0] → fd 3
+		"PYTHONUNBUFFERED=1",  // Python stdout/stderr 不缓冲，print() 立即输出
 	)
 	cmd.ExtraFiles = []*os.File{pr} // fd 3 in child
-	if w.cfg.stdout != nil {
-		cmd.Stdout = w.cfg.stdout
-	} else {
-		cmd.Stdout = os.Stdout
+	prefix := fmt.Sprintf("[python:%d] ", w.id)
+	stdout := w.cfg.stdout
+	if stdout == nil {
+		stdout = os.Stdout
 	}
-	if w.cfg.stderr != nil {
-		cmd.Stderr = w.cfg.stderr
-	} else {
-		cmd.Stderr = os.Stderr
+	stderr := w.cfg.stderr
+	if stderr == nil {
+		stderr = os.Stderr
 	}
+	cmd.Stdout = newPrefixWriter(stdout, prefix)
+	cmd.Stderr = newPrefixWriter(stderr, prefix)
 
 	if err := cmd.Start(); err != nil {
 		pr.Close()