A robotic gripper mechanism has a housing, a gripper arm and a retention projection. The gripper arm extends from the housing. The gripper arm has a gripper finger provided at a distal end thereof. The retention projection is provided on the housing and cooperates with the gripper arm to exert a retention force on the gripper arm. Wherein when an external force is applied to the gripper finger in a direction which is parallel to a longitudinal axis of the housing, the gripper arm will move relative to the housing if the external force is greater than the retention force.