The Philippine Sea is a part of the western Pacific Ocean bordered by the Philippines and Taiwan to the west, Japan to the north, the Marianas to the east and Palau to the south.

The Philippine Plate forms the floor of this sea and it subducts under the Eurasian Plate which formed the Philippine archipelago. Between the two plates is the Philippine Trench.

In 1944, it was the site of the Battle of the Philippine Sea, a World War II naval battle between Japan and the United States.