OBJECTIVE: This study evaluated postoperative complications of percutaneous nephrolithotomy (PCNL)and the influence of selected factors on the risk of complications using the modified Clavienclassification system in East Avenue Medical Center. PATIENTS AND METHODS: All patients who were treated with Percutaneous Nephrolithotomy (PCNL) atEast Avenue Medical Center from January to August 2017 were included. Complications wereevaluated by the modified Clavien classification system. RESULTS: Of the 45 patients with Clavien scores, 5 (11.1%) patients experienced one or morecomplications. Noted complications were fever, pneumothorax, hydrothorax and sepsis. Accordingto the modified Clavien classification, the majority had no complications and classified as Claviengrade 0. CONCLUSION The majority of complications after PCNL are minimal. Longer operative time and age> 59 are associated with the risk of more severe postoperative complications in PCNL.