Zamboanga Sibugay, officially the Province of Zamboanga Sibugay, is a province in the Philippines located in the Zamboanga Peninsula region in Mindanao. Its capital is Ipil and it borders Zamboanga del Norte to the north, Zamboanga del Sur to the east and Zamboanga City to the southwest. To the south lies Sibuguey Bay in the Moro Gulf.
Zamboanga Sibugay is the 79th province created in the Philippines, when its territories were carved out from the third district of Zamboanga del Sur in 2001.
The earliest recorded mention of Sibugay was in Historia de las islas de Mindanao, Jolo y sus adyacentes (1667) by the Spanish priest Francisco Combés, which describes the village of "Sibuguey" along the river Sibuguey.
Zamboanga Sibugay was formerly part of Zamboanga del Sur. Attempts to divide Zamboanga del Sur into two separate provinces date as far back as the 1960s. Several bills were filed in the Philippine Congress, but remained unacted. The new province was finally created by Republic Act No. 8973 signed into law by President Joseph Estrada on November 7, 2000. On February 22, 2001, R.A. 8973 was ratified through a plebiscite conducted in 44 municipalities of Zamboanga del Sur and Pagadian City. Zamboanga del Sur Third District Representative George Hofer was appointed, and later elected as its first governor in 2001.