A theoretical and experimental study is presented for the force control of a miniature gripper driven by piezoelectric bimorph cells. One finger of the gripper is modeled by a flexible cantilever with a force sensor attached to its free end. A pair of piezoelectric bimorph cells are glued to both sides of the cantilever. The mate of the finger is assumed to have adequate stiffness and can be modeled by a rigid beam. In the analysis, the output of the force sensor is defined by the arm tip displacement multiplied by the sensor stiffness. Both the PID control and the digital optimal control scheme are introduced to drive the arm so that the tip produces 0.03 N and maintains the commanded value constantly. It is shown that both the experimental and theoretical results are in good agreement with each other, further the piezoelectric bimorph cells work well as an actuator in minute force control of the gripper.