Epidural steroid injection is one method of releiving chronic back pain. However, problems with the loss of resistance to air technique include the possible subarachnoid or subdural injection of air resulting in headache, venous air embolism, and the introduction of air bubbles into the epidural space. Pneumocephalus is a rare complication of epidural block for epidural steroid injection. We report a case of a 58-year-old woman who developed a severe headache and posterior nuchal pain with incomplete oculomotor palsy due to pneumocephalus occuring after an epidural steroid injection.