A new micro gripper based on piezoelectric bimorph was designed. Inspired by the fact that the substance of piezoelectric crystal deformation is polarization and the relation between polarization and induced surface charge, the griping force and displacement self sensing method based on integral charge was proposed, and the mathematical models of griping force and displacement referring to the Smits’ piezoelectric cantilever static model was established.The results show that the displacement obtained by self sensing method and by independent sensor had good consistency in the case of static or low frequency.By using electronic micro balance,experimental results verified the effectiveness of the self sensing griping force method.Although the griping force obtained by self sensing method (the maximum was 0.072 N) was greater than the one by electronic micro balance (the maximum was 0.052 N),the self sensing force results could well reflect the true griping force by coefficient correcting of the force.