Abstract: In order to grasp objects dexterously and stably by robot,this paper proposes a new structure for four-fingered and twelve-joint gripper based on single motor driving.The motor drives a cross-linkage,whose terminal connects the first power rod of each finger.Every finger has three joints,and two knuckles each with a parallelogram structure ensure the translational motion of fingertip.The second power rod of each finger has a prolonged chute,and the specially designed chute shifts around a fixed fulcrum to realize the fingertip uniform motion while the second power rod moves.The new design scheme of the single motor driven gripper is of simple control and solid grasp.