In this paper, we present an interactive smart TV control system, which functions via recognition of hand gesture. This system consists of two subsystems. One is for the detection of the hand and recognition of the hand gesture, the other is for the user graphic user interface, which is commanded by the user's gesture. The gesture recognition subsystem has two major components: hand detection and tracking and gesture recognition. In addition to the gesture recognition, a face recognition module has been added for personalized services such as favorite channels or parental guidance, etc. Face recognition requires three modules: face registration, face detection, and face verification. We have defined several natural gestures for natural interactions between the user and smart TV, and suggest a method for robust detection and recognition.