Pulau Thitu, juga dikenal sebagai Pulau Pag-asa (bahasa Tagalog:Pulo ng Pag-asacode: tl is deprecated ; bahasa Pangasinan:Ilalocode: pag is deprecated ; Hokkien Min NanHanzi:鐵峙/铁峙; Pe̍h-ōe-jī:Thih-tu; harfiah: 'Iron Shoal'; MandarinHanzi:中業島/中业岛; Pinyin:Zhōngyè Dǎo; bahasa Vietnam:Đảo Thị Tứcode: vi is deprecated ), yang memiliki luas 372 hektare (920 ekar), adalah sebuah pulau terbesar kedua di Kepulauan Spratly[3] dan pulau terbesar di kepulauan yang diurus oleh Filipina. Pulau tersebut berjarak sekitar 480 kilometer (300mi) dari barat Puerto Princesa.
↑Note that in 2014 the PRC embarked on a number of reclamation projects in the Spratly Islands. It appears that the largest of these, at Fiery Cross Reef, is of at least 60 hectares, and according to some unverifiable sources, possibly as large as 150 hectares. Kristine Kwok and Minnie Chan (8 June 2014). "China plans artificial island in disputed Spratlys chain in South China Sea". South China Morning Post. Diakses tanggal 28 September 2014.