In chronic ambulatory hemiplegic patients, structural changes might be developed at both ankles possibly due to unequal and repetitive weight bearing on tendons and ligaments. We examined ankles by sonography to find out structural changes of tendons and ligaments of both ankles in ambulatory hemiplegic patients. Nineteen ambulatory hemiplegic patients over 1 year were included as study subjects. All subjects had no previous trauma or disease history in their ankle joints and they were able to walk independently or with supervision but had spastic ankles with equinovarus tendency. We examined both ankle joints by sonography to see joint effusion and measure width, thickness, and area of tendons of the tibialis anterior, tibialis posterior, and Achilles, and also ligaments of the anterior talofibular and calcaneofibular. We compared sonographic features of the hemi-side ankle with the sound-side ankle. There were no significant differences between hemi-side and sound-side ankles in almost all measured parameters of tendons and ligaments. However, the width of the hemi-side tibialis posterior tendon (8.61±1.37 mm) was narrower than the sound-side tendon (7.24±1.52 mm). With the amount of active joint motion and weight bearing possibly preventing ligament and tendon atrophy even though marked weakness, spasticity occurred during the chronic hemiplegic phase.