Osmaniye Province (Turkish: Osmaniye ili) is a province in south-central Turkey. It was named Cebel-i Bereket (lit. 'Fertile Mountain') in the early republic until 1933, when it was incorporated into Adana Province. It was made a province again in 1996. Its area is 3,320 km², and its population is 559,405 (2022). The province is situated in Çukurova, a geographical, economical and cultural region. The capital of the province is Osmaniye. Other major towns include Kadirli and Düziçi.

Osmaniye Province is mainly under hot-summer Mediterranean climate (Csa) according to Köppen climate classification system.

Osmaniye province is divided into 7 districts (capital district in bold):

37°13′41″N 36°12′45″E / 37.22806°N 36.21250°E / 37.22806; 36.21250