Gripper with two claws of automatic placing and removing manipulator is designed in this paper, and structure characteristics, working theory and positional error analysis are introduced. This gripper has the function of automatic center aligning and size control. The chucking size of gripper can be modified automatically in order to be adaptable when clamping different work pieces and this gripper, which could shorten the time and improve the efficiency, is designed to place and remove workpiece at one time beat. The gripper has a virtue of better ability to locate and move, improving the precision of automatic feeding manipulator and lathe cutting. The grippers have the advantages of simple structure, small volume and weight, which can solve the problems of complicated structure and massive volume for typical translational gripper. They also could simplify the control system of manipulator; meet the demand of placing and removing workpiece instead of complicated and heavy manual work.