Moving target positioning on monocular camera is one of the basic task of visual tracking,visual sensor is the essential part for the acquisition of the target point position and other spatial information．According to the monocular camera pinhole model, the world coordinates of the moving object and the two-dimensional coordinates of the image are mapped to the three-dimensional coordinates of the camera coordinate system by using geometric relation. Calibrate camera’s height and rotation parameters, on the basis of this, the target position coordinates can be calculated. Take the even variable speed motion as a model. When the moving target is blocked, the acceleration and velocity can be determined according to the previous position information and the acceleration is adaptively updated. The equation of state of moving target is established and the position of target is predicted by Kalman filtering. The real position is replaced by the estimated position. Estimate the subsequent motion state and search the moving target at the estimated position so that the blocked moving target can be tracked. Experimental results show that this method is feasible and the moving target can be located and tracked when it is blocked.