In order to realize the safe and efficient movement of the robot, the method of constructing the grid map with local uncertainty of a mobile robot based on Kinect sensor is proposed. The robot's working environment is divided into three parts: the free area, the obstacle area and the unknown area. Kinect sensor is used to detect each area and determine the confidence level of the obstacles. Finally, the local grid map of the robot environment is constructed. Taking the wheeled mobile robot as the experimental platform, the possibility of the proposed algorithm is verified.