INPEX Corporation (国際石油開発帝石株式会社, Kokusai Sekiyu Kaihatsu Teiseki Kabushiki-gaisha^?) (literally, INternational PEtroleum EXploration Corporation; hence the short name INPEX) is a Japanese oil company established in 1966 as North Sumatra Offshore Petroleum Exploration Co., Ltd.

In 2006, INPEX acquired Japanese oil company Teikoku Oil.

INPEX created a venture company called INPEX Browse, Ltd on 1 September 1998. This was for a previously wholly owned INPEX project in the offshore Basin off the north west coast of Western Australia where a gas-field was discovered in the WA-285-P permit area. The official name of the proposed development project will be the Ichthys (gas-field) Development, which the company wanted to base on the Maret Islands. After farming out 24% of the permit ownership to Total S.A's subsidiary Total E&P Australia the concept and location was changed.

The location of this project, and the issue of industrialising the Kimberley coast is under discussion in Australia. Environmentalists and local ecotourism operators are concerned about industrial infrastructure destroying the pristine nature of this coast line.