We describe a case of a high-pressure polyurethane injection injury to the hand, and discuss how its management differs from other injection injuries. A male patient was transferred to our hospital due to persistent purulent discharge from the 2nd finger, which began 15 days after the injury. The injected foreign body, polyurethane, could not be recognized by the patient and was not indicated radiographically. During surgery, the polyurethane foam was removed. The patient had no functional impairment 24 months after surgery.