Objective The single leg support tree pose and Yan balace of yoga was selected to compare the biomechanical characteristics of lower limb joint angles, joint force and muscle strength for professional and non-professional yoga practitioners, so as to provide theoretical basis for scientific fitness of yoga beginners and exercise prescription determined by rehabilitation physicians. Methods BTS infrared motion capture system was used to collect kinematic data, Kistler forceplate was used to collect dynamic data, AnyBody 7.0 simulation software was used to calculate the joint force and muscle strength, and Biodex balance system was used to evaluate the stability of single support. Results In both tree pose and Yan balance, the muscle strength of lower limbs in professional group was greater than that in non-professional group. Support leg of tree pose: the muscle strength of the tibialis anterior, gluteus medius posterior, iliac medialis and sartorius in professional group was greater than that in non-professional group (P<0.05). Balance leg of tree pose: the muscle strength of the biceps femoris breve, sartorius, piriformis, gemellus inferior, iliac lateralis, iliac medialis, gluteus maximus inferior, obturator internus in professional group was greater than that in non-professional group (P<0.05). Support leg of Yan balance: the muscle strength of tibialis anterior, extensor digitorum longus, extensor hallucis longus, obturator internus, gluteus maximus superior in the professional group was greater than the non-professional group (P<0.05). Balance leg of Yan balance: The muscle strength of extensor hallucis longus in professional group was greater than that in non-professional group (P<0.05). The scores of front-rear, overall of PS-BI, overall, front-rear, left-right of athlete single leg (ASL) in professional group were significantly lower than those in non-professional group (P<0.05). Conclusions The joint angle will affect the degree of muscle exercise in lower limbs. During yoga practice, attention should be paid to the standard of postures and the exercise of corresponding muscles. In tree pose, the muscle strength of both legs in non-professional group was significantly different from that in professional group, and the difference in Yan balance was more obvious on the supporting leg. Yoga practice can improve the stability of single leg support in multiple directions.