Objective To evaluate the effect of the knee and ankle joint angles on the stiffness of triceps surae in healthy men by shear wave elastography (SWE). Methods Twenty male healthy volunteers who underwent physical examination in Guangdong Provincial Hospital of Chinese Medicine from January 2021 to June 2021 were collected. Under the condition of full knee extension (0 °) or flexion (90 °), SWE was used to assess the muscle stiffness at 25° dorsiflexion, 0° and 50° plantar flexion of the ankle. Results The stiffness of medial head of gastrocnemius(MG), lateral head of gastrocnemius(LG) and soleus (Sol) in knee extension position was significantly higher than that in knee flexion position at different ankle angles (P0.05). When knee flexion was 90°, only LG and sol stiffness increased with the increase of ankle dorsiflexion angle (P