Inflammatory orbital pseudotumor is a benign space-occupying lesion of unknown origin that involves all or part of the fatty tissue within the orbit. Occasionally the disease may extend into the middle cranial, the pterygopalatine, and the infratemporal fossa through the various foramina of the orbit, although extension into the infratemporal fossa is very rare. We present a case which extends into the infratemporal fossa through the inferior orbital fissure, resulting in presenting symptoms mimicking temporomandibular joint dysfunction.