Suspensionplasty was performed using the abductor pollicis longus tendon for osteoarthritis at the carpometacarpal joint of the thumb. The operated wrist had a full range of motion four months after operation; however, there was swelling on the dorsoradial aspect of the wrist and, upon terminal wrist extension, pain was present at the maximum dorsiflexion. Suddenly, one year after operation the patient could not extend the interphalangeal joint of the thumb. Surgical exploration revealed rupture of the extensor pollicis longus tendon. Tenosynovitis at the extensor carpi radialis brevis tendon, where the abductor pollicis longus tendon is sutured, might cause extensor pollicis longus tendon rupture. Late postoperative complications such as this extensor pollicis longus tendon rupture after suspensionplasty using the abductor pollicis longus tendon are extremely rare and this is the first case in the literature.