This paper presents a novel model of snake-like robots based on a spatial linkage mechanism. The reasonable structural parameters of the mechanism are obtained by performing a kinematic simulation. Then the kinematics of the spatial linkage mechanism is developed and the motor angles of the robot for performing lateral undulation are analyzed based on the Serpenoid curve. The torque of servomotors at each moment is also obtained. The experiments detailed in this paper confirm that the robot is of the ability to realize several motion modes, including lateral undulation, left and right turning motions, and uplifting of the head.