Oecussi-Ambeno (also Ocussi) is a province of East Timor. It is located on the western part of Timor island, which is a part of Indonesia. The capital of the province is Pante Makasar, also called Ocussi town.

It was in Pante Makasar that an Indonesian fifth column raised the Indonesian flag and took control of O-A on 8 December, 1975, a day after the Indonesian invasion of East Timor proper.

It has been considered to be an enclave but it has sea access.