An ulnar nerve injury can be seen in neurosurgery or neurology, as well as orthopedics or trauma orthopedics. The ulnar nerve is one of the components of the peripheral nerves that innervate specific muscles in the upper extremities as well as the skin tissue for motor as well as sensory functions, but there are many factors that can lead to damage to the functional structure of the ulnar nerve. Individuals with unexplained ulnar nerve injuries are generally advised to consult a neurologist in a specialized hospital, specifically in the Department of Neurosurgery or Neurology. If the ulnar nerve injury occurs due to trauma caused by external violence directly on the upper limb, you can consult neurosurgery, orthopedics or trauma orthopedics. In conclusion, ulnar nerve injury and the cause of which department is closely related to the cause of ulnar nerve injury caused by different causes of ulnar nerve injury is suitable for diagnosis and treatment in different departments. It is recommended that patients who have ulnar nerve injury should seek medical treatment in time.