Combination of various dynamic motions may lead to better performance of dynamic motion tasks by utilizing the energy transfer between the motions. We have developed a robot capable of doing sequential jumping-stepping motion for agile locomotion. The robot is a musculoskeletal humanoid robot that mimics human skeletal system and muscular system with pneumatic artificial muscles as the actuators. For realizing the motion, we decide muscle control command for each motion referring to the muscle activation pattern of a human. We have conducted experiments for the sequential jumping-stepping motion with our motion strategy on the developed musculoskeletal robot. The results show that the musculoskeletal robot performs faster stepping by performing pre-jumping before a stepping than stepping without pre-jumping. We have also found that proper timing of landing command became crucial for the stepping motion performance.