diff --git a/acl_commands.go b/acl_commands.go
index a7b5dd24..0a8a195c 100644
--- a/acl_commands.go
+++ b/acl_commands.go
@@ -70,7 +70,12 @@ func (c cmdable) ACLSetUser(ctx context.Context, username string, rules ...strin
 }
 
 func (c cmdable) ACLGenPass(ctx context.Context, bit int) *StringCmd {
-	cmd := NewStringCmd(ctx, "acl", "genpass")
+	args := make([]interface{}, 0, 3)
+	args = append(args, "acl", "genpass")
+	if bit > 0 {
+		args = append(args, bit)
+	}
+	cmd := NewStringCmd(ctx, args...)
 	_ = c(ctx, cmd)
 	return cmd
 }
diff --git a/acl_commands_test.go b/acl_commands_test.go
index e6a99ec5..d2cb17a7 100644
--- a/acl_commands_test.go
+++ b/acl_commands_test.go
@@ -109,6 +109,14 @@ var _ = Describe("ACL user commands", Label("NonRedisEnterprise"), func() {
 		Expect(password).NotTo(BeEmpty())
 	})
 
+	It("gen password with length", func() {
+		bit := 128
+		password, err := client.ACLGenPass(ctx, bit).Result()
+		Expect(err).NotTo(HaveOccurred())
+		Expect(password).NotTo(BeEmpty())
+		Expect(len(password)).To(Equal(bit / 4))
+	})
+
 	It("setuser and deluser", func() {
 		res, err := client.ACLList(ctx).Result()
 		Expect(err).NotTo(HaveOccurred())