diff --git a/example.lsp b/example.lsp
index 77dbff6..5a6f74e 100644
--- a/example.lsp
+++ b/example.lsp
@@ -2,7 +2,7 @@
 (let ((ctrlc (format nil "~A" (convert 3 <character>))))
   (block main
     (while t
-      (case (expect* "xxx" "yyy")
+      (case (expect* 'timeout 10 "xxx" "yyy")
         ((0)
          (sendln (string-append ctrlc "exit"))
          (return-from main nil)
@@ -10,4 +10,11 @@
         ((1)
          (sendln (string-append ctrlc "rem"))
          )
-        ))))
+        ((-1)
+         (sendln (string-append ctrlc "exit"))
+         (return-from main nil)
+        )
+        )
+      )
+    )
+  )
diff --git a/global.go b/global.go
index 8394e21..fa31793 100644
--- a/global.go
+++ b/global.go
@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"io"
+	"time"
 
 	"github.com/hymkor/gmnlisp"
 )
@@ -41,11 +42,39 @@ func (g *Global) spawn(ctx context.Context, w *gmnlisp.World, args []gmnlisp.Nod
 	return gmnlisp.Null, nil
 }
 
-func (g *Global) expect(ctx context.Context, w *gmnlisp.World, args []gmnlisp.Node) (gmnlisp.Node, error) {
-	patterns := make([]string, 0, len(args))
-	for _, arg := range args {
-		patterns = append(patterns, arg.String())
+var symTimeout = gmnlisp.NewSymbol("timeout")
+
+func (g *Global) expect(ctx context.Context, w *gmnlisp.World, node gmnlisp.Node) (gmnlisp.Node, error) {
+	patterns := []string{}
+	timeOut := 0
+
+	for gmnlisp.IsSome(node) {
+		var value gmnlisp.Node
+		var err error
+
+		value, node, err = w.ShiftAndEvalCar(ctx, node)
+		if err != nil {
+			return nil, err
+		}
+		if symTimeout.Equals(value, gmnlisp.EQUALP) {
+			value, node, err = w.ShiftAndEvalCar(ctx, node)
+			if err != nil {
+				return nil, err
+			}
+			_timeout, err := gmnlisp.ExpectClass[gmnlisp.Integer](ctx, w, value)
+			if err != nil {
+				return nil, err
+			}
+			timeOut = int(_timeout)
+		} else {
+			patterns = append(patterns, value.String())
+		}
+	}
+	var result int
+	if timeOut == 0 {
+		result = g.w.Expect(patterns...)
+	} else {
+		result = g.w.ExpectWithTimeout(time.Second*time.Duration(timeOut), patterns...)
 	}
-	result := g.w.Expect(patterns...)
 	return gmnlisp.Integer(result), nil
 }
diff --git a/main.go b/main.go
index 9619d96..f1c720e 100644
--- a/main.go
+++ b/main.go
@@ -30,7 +30,7 @@ func mains(args []string) error {
 		gmnlisp.Functions{
 			gmnlisp.NewSymbol("sendln"):  gmnlisp.Function1(g.sendln),
 			gmnlisp.NewSymbol("spawn"):   &gmnlisp.Function{Min: 1, F: g.spawn},
-			gmnlisp.NewSymbol("expect*"): &gmnlisp.Function{Min: 1, F: g.expect},
+			gmnlisp.NewSymbol("expect*"): gmnlisp.SpecialF(g.expect),
 		})
 
 	if len(args) <= 0 {