Zamboanga Sibugay (Cebuano: Probinsya sa Zamboanga Sibugay, Chavacano: Provincia de Zamboanga Sibugay, Filipino: Lalawigan ng 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. Hence it the fourth newest province, being before Shariff Kabunsuan (October 2006), Dinagat Islands (December 2006) and Davao Occidental (2013).

Zamboanga Sibugay was formerly part of Zamboanga del Sur. Attempts to divide Zamboanga del Sur into 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 passed on November 7, 2000 and signed into law by President Gloria Macapagal-Arroyo on February 24, 2001. Zamboanga del Sur Third District Representative George Hofer was elected as its first governor in 2001.