This paper describes the mechanism and vertical jumping pattern of a one-legged jumping robot that can mimic the muscular and skeletal system of a human leg. The jumping robot has a waist, a thigh, a shin, a foot, and a toe. Its weight is 12.34 kg, and its height is 1010 mm. It has a total of 13 actuators: 10 mono-articular types and 3 bi-articular types. Two kinds of pneumatic artificial muscles such as mono-articular and bi-articular muscles are installed in the rear and the front of the thigh and shin to antagonize each other. For a vertical jump, a joint angle pattern is developed based on the linear and angular momentum. The effectiveness of the mechanism and the jumping pattern of the robot are verified through simulations and experiments.