OBJECTIVE: Peroneus longus tendon (PLT) has become a reliable autologous graft option for various ligament reconstructions. But there are potential risks and complications associated with its use as a graft. This retrospective study aimed to examine the complications and donor site morbidity following PLT harvesting. PATIENTS AND METHODS: A retrospective review was performed on an institutional digital patient database, and all patients who underwent ligament reconstruction using PLT autograft were identified. Intraoperative, early, and late complications were reviewed using digital patient notes and patients underwent a complete physical examination during their final follow-up. Ankle function was assessed using the AOFAS score, and manual ankle muscle testing was performed on both sides. Sural nerve iatrogenic injury was evaluated with a dermatomal light touch examination. Cosmetic satisfaction due to incision scar and footwear complaints were also assessed. RESULTS: 82 patients (74 male, eight female) with a mean age of 31.9 ± 10.4 years (range, 16-66) were included in the final analysis. The mean follow-up time was 46.6 ± 30.3 months (range, 6-109). The mean AOFAS score for the donor side was 98.7 ± 3.3 (range, 87-100), and the contralateral side score was 100, with manual muscle testing graded as 5 in all movements and similar to the contralateral side. Fifteen patients (18.3%) had hypoesthesia over the dorsolateral aspect of the foot distal to the incision scar, two patients (2.4%) had hyperalgesia over the distal incision scar, and one patient (1.2%) had mild ankle instability. There were two cases (2.4%) of compartment syndrome, both of which were treated with fasciotomy and had complete regression of symptoms after 5 days. One patient (1.2%) had a transient peroneal nerve injury and foot drop that resolved in the sixth month. CONCLUSIONS: The results of this retrospective study suggest that harvesting the PLT is associated with a high rate of complications and donor site morbidity. The most common complication was hypoesthesia around the lateral side of the foot, although the ankle functions were not affected significantly. Two cases of compartment syndrome and one transient peroneal nerve injury were observed. Care should be taken while harvesting PLT autograft, and it should be kept in mind that peroneal nerve injury might occur. LEVEL OF EVIDENCE: Level IV, retrospective case series.