The Timor Sea is the stretch of the Pacific Ocean situated between the island of Timor, now split between the states of Indonesia and East Timor, and the Northern Territory of Australia. The waters to the east are known as the Arafura Sea , to the west lies the Indian Ocean.

Beneath the Timor Sea lie considerable reserves of oil and gas. There is a dispute between Australia and East Timor over the exploitation right in an area known as the Timor Gap . This is the area where Australia's territorial claim, which extends to the bathymetric axis (the line of greatest sea-bed depth), overlaps that of East Timor, which follows the former colonial power Portugal in claiming the dividing line should be midway between the two countries.