Myofascial pain syndrome is defined as the sensory, motor and autonomic symptoms caused by the myofascial trigger points. The sternocleidomastoid muscle is a complex muscle that frequently contains multiple trigger points. These trigger points cause symptoms that are easily misdiagnosed as other conditions. Earache of unexplained origin is likely to be caused by trigger points in the clavicular division of the sternocleidomastiod muscle. The authors report a case of earache caused by a trigger point in the sternocleidomastoid muscle. A 34 year-old woman had earache without any history of trauma or infection. The patient did not have any abnormal finding by otolaryngologic testing, except for an earache, which had not subsided. On physical examination, trigger points in the clavicular division of the sternocleidomastiod muscle were found, and the earache was successfully treated by trigger point injections.