Abstract: A shape control algorithm for soft robot inspired by octopus is presented. Because of the infinite degrees of freedom of soft robot, the control algorithm for the rigid robot is not applicable. According to the movement characteristics of soft robot, the shape control parameters are derived. Then the kinematics model of the soft robot is developed, and the relation between soft robot shape parameters and driving cables length is deduced. From this relation, a shape control algorithm is designed. The stability of the shape control algorithm is proved through Lyapunov theory. Finally, the effectiveness of the shape control algorithm is verified by experiments.