The Pneumatic Artificial Muscle (PAM) actuator has played a role to the robotics application especially end-effector of manipulated robot, which yields remarkable muscle-like properties such as high force to weight ratio, soft and flexible structure. This paper develops a mechanism of PAM robot hand based on adaptive robotic gripper concept for applying to the various tasks. The proposed concept of PAM robot hand is suitable to grasp the object in different shapes. The outcome of this PAM robot hand is the three fingers robot hand. This PAM robot hand requires only two actutors since the fingers of robot hand are designed to have a synchronized motion with each other. The empirical models of both mechanical actuation of robot hand and fluid dynamic of pressurized gas within PAM are determined systematically where their interactions comply with the continuity principle and energy balance in describing actual dynamic behaviors of the PAM robot hand. The optimal controller is applied to control the performance of this PAM robot hand under several conditions of tasks. These manipulations result in desired mechanical actuation of the PAM robot hand in practical uses.