What is largest sea?

Philippine Sea. The Philippine Sea is the largest sea in the world, covering an area of approximately 1,351,000 square kilometers (522,000 square miles). It is located in the western Pacific Ocean, and is bounded by the Philippines, Taiwan, Japan, and Palau. The Philippine Sea is a deep sea, with an average depth of 4,000 meters (13,000 feet). The deepest point in the Philippine Sea is the Mariana Trench, which is the deepest point in the world's oceans, at 11,034 meters (36,201 feet).