Sepia tokioensis is a species of cuttlefish native to the western Pacific Ocean, specifically Japanese waters from Tsugaru Strait to Kyūshū and the Ohsumi Islands, including Sagami Bay, Suruga Bay, the western Japan Sea, and Shimane Prefecture. It lives on the continental shelf.
Sepia tokioensis grows to a mantle length of 90 mm.
The type specimen was collected in Tokyo Bay and is deposited at the Musee Zoologique in Strasbourg.