Abstract: A tumbling robot named Tumbot with jumping capability is designed. Tumbot moves mainly depending on tumbling with jumping as an auxiliary locomotion pattern. It is a small irregular trapezoidal robot which is 12.5cm long, 12cm wide, 4cm high, and about 275g in weight. It has two 11cm long arms on its left and right sides respectively for achieving tumbling locomotion. An improved six-bar gear mechanism is adopted to store elastic energy, which can load four torsion springs and two tension springs. The robot jumps when the stored energy is released by an incomplete gear of the gearbox. The body of the robot is symmetrical at both ends which enables continuous jumping locomotion with no need of self-righting mechanism. The tumbling mechanism also can be used to adjust the jumping direction and takeoff angle of the robot. The mechanism design, force analysis, simulations, and experiments have been done. Experimental results show that Tumbot can move forward at a speed of 7.04cm/s, crawl over the 3.5cm high step. Its maximum jumping height is 51cm. The basic locomotion capabilities of the robot prove to be effective for rough terrain.