A 43-year-old female patient with a left L5 radiculopathy was referred to our pain clinic for an epidural steroid injection. An epidural puncture was done at the L4-5 intervertebral space with the loss of resistance technique using air. There was no CSF leaKage during the procedure. After 6 ml of air was injected, she complained of a sudden severe headache, nausea, tinnitus, and mild hearing difficulty. The headache was localized at the left temporal and suboccipital area and the nature of it was constant, squeezing, and non-throbbing. Neurological examination was normal except a mild sensory change on the right face and right hemibody. A brain CT disclosed sudural and subarachnoid pneumocephalus. Twenty-four hours after the event, she was discharged without any specific complaints. To avoid pneumocephalus during epidural puncture, saline instead of air is highly recommended. If physicians use air, a small volume should be used and careful evaluation of the patients condition during injection despite no CSF leaKage should be done.