Background: Pain guidelines suggest transcutaneous electrical nerve stimulation (TENS) as a reliable analgesic method in postoperative pain. Objectives: This study was conducted as a randomized controlled study to determine the effect of TENS on postoperative pain and analgesic consumption in patients who have undergone posterolateral thoracotomy (PLT). Design: The study was conducted in the Thoracic Surgery Clinic of a university hospital with 40 patients (test group: 20, control group: 20) and its power was 99%. While, test group patients were administered TENS, the control group patients were not. The pain assessment and analgesic consumption in both groups were recorded. Results: The pain levels and analgesic consumption of the test group were lower than that of the control group (p<.05). Conclusions: TENS reduced PLT pain and analgesic consumption. Thus, TENS can be recommended as an easy and reliable analgesic method in PLT.