Electrical burn injury causing bilateral patellar ligament destruction leading to complete loss of knee extension is a very rare injury. In such situation, surgical repair or reconstruction of the patellar ligament becomes necessary to restore knee functions. Here, we present such a case of an 8-year-old boy, whose both patellar ligaments were destroyed throughout its length due to high-voltage electrical injury. His left knee joint cavity was exposed and grossly infected, but the right knee joint cavity was apparently intact. The right-sided patellar ligament was reconstructed with an ipsilateral and looped semitendinosus tendon graft and covered with a medial gastrocnemius musculocutaneous flap. The patient had an uneventful recovery, and full range of motion in the right knee joint along with good bipedal locomotion was achieved successfully.