diff --git a/.github/workflows/pr-test.yml b/.github/workflows/pr-test.yml
index d9fb8a1d..df537ab2 100644
--- a/.github/workflows/pr-test.yml
+++ b/.github/workflows/pr-test.yml
@@ -889,7 +889,10 @@ jobs:
         env:
           YAO_SANDBOX_WORKSPACE: ${{ runner.temp }}/sandbox/workspace
           YAO_SANDBOX_IPC: ${{ runner.temp }}/sandbox/ipc
-        run: make unit-test-sandbox
+        run: |
+          # Use runner's UID:GID to avoid permission issues
+          export YAO_SANDBOX_CONTAINER_USER="$(id -u):$(id -g)"
+          make unit-test-sandbox
 
       - name: Codecov Report
         uses: codecov/codecov-action@v4
diff --git a/.github/workflows/unit-test.yml b/.github/workflows/unit-test.yml
index 9d36cd18..79a1f5b7 100644
--- a/.github/workflows/unit-test.yml
+++ b/.github/workflows/unit-test.yml
@@ -659,7 +659,10 @@ jobs:
         env:
           YAO_SANDBOX_WORKSPACE: ${{ runner.temp }}/sandbox/workspace
           YAO_SANDBOX_IPC: ${{ runner.temp }}/sandbox/ipc
-        run: make unit-test-sandbox
+        run: |
+          # Use runner's UID:GID to match host permissions
+          export YAO_SANDBOX_CONTAINER_USER="$(id -u):$(id -g)"
+          make unit-test-sandbox
 
       - name: Codecov Report
         uses: codecov/codecov-action@v4
diff --git a/sandbox/config.go b/sandbox/config.go
index b73b5542..f6335c5e 100644
--- a/sandbox/config.go
+++ b/sandbox/config.go
@@ -20,6 +20,7 @@ type Config struct {
 	// Container internal paths
 	ContainerWorkDir   string `json:"container_workdir,omitempty"`    // Container working directory, default: /workspace
 	ContainerIPCSocket string `json:"container_ipc_socket,omitempty"` // Container IPC socket path, default: /tmp/yao.sock
+	ContainerUser      string `json:"container_user,omitempty"`       // Container user, default: "" (use image default). Set to "0" for root.
 }
 
 // DefaultConfig returns a Config with default values
@@ -110,4 +111,9 @@ func (c *Config) Init(dataRoot string) {
 	} else if c.ContainerIPCSocket == "" {
 		c.ContainerIPCSocket = "/tmp/yao.sock"
 	}
+
+	// Container user (for CI environments with UID mismatch)
+	if env := os.Getenv("YAO_SANDBOX_CONTAINER_USER"); env != "" {
+		c.ContainerUser = env
+	}
 }
diff --git a/sandbox/config_test.go b/sandbox/config_test.go
index 60bc0a78..f52d53b0 100644
--- a/sandbox/config_test.go
+++ b/sandbox/config_test.go
@@ -27,6 +27,10 @@ func TestDefaultConfig(t *testing.T) {
 }
 
 func TestConfigInit(t *testing.T) {
+	// Clear any existing environment variables that might interfere
+	os.Unsetenv("YAO_SANDBOX_WORKSPACE")
+	os.Unsetenv("YAO_SANDBOX_IPC")
+
 	// Test with dataRoot
 	cfg := &Config{}
 	cfg.Init("/tmp/yao-test")
diff --git a/sandbox/manager.go b/sandbox/manager.go
index 37238c2c..d47651c6 100644
--- a/sandbox/manager.go
+++ b/sandbox/manager.go
@@ -162,6 +162,7 @@ func (m *Manager) createContainer(ctx context.Context, userID, chatID string) (*
 		Image:      m.config.Image,
 		Cmd:        []string{"sleep", "infinity"},
 		WorkingDir: m.config.ContainerWorkDir,
+		User:       m.config.ContainerUser, // Empty string uses image default
 		Env: []string{
 			"YAO_IPC_SOCKET=" + m.config.ContainerIPCSocket,
 		},
diff --git a/sandbox/manager_test.go b/sandbox/manager_test.go
index b8b8148b..a57a1229 100644
--- a/sandbox/manager_test.go
+++ b/sandbox/manager_test.go
@@ -40,6 +40,11 @@ func getTestDirs(prefix string) (string, string, string, error) {
 	return workspaceRoot, ipcDir, tmpDir, nil
 }
 
+// getContainerUser returns the container user from environment variable
+func getContainerUser() string {
+	return os.Getenv("YAO_SANDBOX_CONTAINER_USER")
+}
+
 // skipIfNoDocker skips the test if Docker is not available
 func skipIfNoDocker(t *testing.T) *Manager {
 	t.Helper()
@@ -57,6 +62,7 @@ func skipIfNoDocker(t *testing.T) *Manager {
 		IdleTimeout:   1 * time.Minute,
 		MaxMemory:     "512m",
 		MaxCPU:        0.5,
+		ContainerUser: getContainerUser(),
 	}
 
 	m, err := NewManager(cfg)
@@ -545,6 +551,7 @@ func TestConcurrencyLimit(t *testing.T) {
 		IdleTimeout:   1 * time.Minute,
 		MaxMemory:     "256m",
 		MaxCPU:        0.25,
+		ContainerUser: getContainerUser(),
 	}
 
 	m, err := NewManager(cfg)
@@ -674,6 +681,7 @@ func TestCleanup(t *testing.T) {
 		IdleTimeout:   100 * time.Millisecond, // Very short for testing
 		MaxMemory:     "256m",
 		MaxCPU:        0.25,
+		ContainerUser: getContainerUser(),
 	}
 
 	m, err := NewManager(cfg)
@@ -748,6 +756,7 @@ func TestManagerWithYaoApp(t *testing.T) {
 		IdleTimeout:   5 * time.Minute,
 		MaxMemory:     "1g",
 		MaxCPU:        1.0,
+		ContainerUser: getContainerUser(),
 	}
 
 	m, err := NewManager(cfg)
@@ -836,6 +845,7 @@ func TestEnsureImageAutoPull(t *testing.T) {
 		IdleTimeout:   1 * time.Minute,
 		MaxMemory:     "128m",
 		MaxCPU:        0.25,
+		ContainerUser: getContainerUser(),
 	}
 
 	m, err := NewManager(cfg)