We report a case of anterior choroidal artery territory infarction due to internal carotid artery dissection presumably caused by scuba diving. A 44-year-old man presented with left facial palsy and hemiparesis. He had a history of scuba diving for 18 months. His last dive was 7 days ago, and he skipped decompression practice at that dive. We assumed that repetitive traumas and microbubbles during scuba diving, which made endothelium vulnerable to damage may have caused a carotid dissection.