Purpose: To present physical therapy results of a patient who had peroneal tendon instability (PTI) surgery. Methods: The foot of the patient who went to hospital with ankle inversion sprain was casted for 10 days. Patient applied to the clinic 10 days after the removal of cast. It was noticed that there was instability in patient’s peroneal tendon in the first treatment day and the pa-tient was transferred to orthopedics clinic. After 10 days, proxi-mal peroneal retinaculum and peroneal tendon were repaired with PTI diagnosis. Two weeks after the 6-week immobilization, physiotherapy program was started. Patient was taken under the treatment for 3 days/week, during 4 weeks. Pain with visual analog scale, range of motion (ROM) with goniometer, edema and atrophy with circumferential measurement were evaluated before and after treatment. In first week, cold pack, electrical sti-mulation to peroneal muscle, stretching exercise to ankle, active joint movements of ankle, and weight transmission exercises were performed. In second week, strengthening exercises with therabant for lower limb extremity, proprioceptive training; in third week one foot balance, walking on treadmill, and in fourth week one foot balance on soft ground, walking on fingertip and heel exercises were added. Results: Edema and atrophy were found before treatment. No pain was observed before and af-ter treatment. Edema and atrophy were decreased; ROM was increased after treatment. Discussion: In literature, studies on physical therapy after PTI surgery were rare. Physiotherapy that is improved by the patient’s development condition after PTI surgery was seen to give successful results.