The invention discloses an artificial lower limb system based on pneumatic muscle. Muscle of people is simulated by pneumatic muscle so as to drive hip joints, knee joints and ankle joints to move, and the artificial lower limb system has the function of completely simulating the movement of lower limbs of people. An artificial lower limb comprises a pelvis, a thighbone, a fibula, a foot, pneumatic muscle and a fibular muscle connecting plate, the pneumatic muscle which is used for simulating the effects of internal obturator muscle, quadratus femoris, pectineal muscle, breviductor, adductor magnus, musculi adductor longus, gluteus medius, piriformis, gluteus maximus and iliopsoas is used for driving the thighbone to bend, stretch, retract, extend and annularly rotate; biceps femoris muscle, adductor magnus, semitendinosus and semimembranosus are simulated to drive the thighbone and the fibula to bend, stretch, retract, extend and annularly rotate; soleus, short peroneal and tibialis anterior muscle are simulated to drive the foot to bend, stretch, retract, extend and annularly rotate; and musculi flexor pollicis longus, extensor longus pollicis, musculi flexor digitorum longus andextensor digitorum longus are simulated to drive five toes to bend and stretch. The artificial lower limb system has the advantages of compact structure, cleanness and good explosion-proof performance and can be used for medical diagnosis, teaching demonstration, exoskeleton rehabilitation training and athletic training of athletes.