Hậu Nghĩa was a former province of South Vietnam located to the west of Saigon. The region shared a border with Cambodia and served as a significant administrative area during the mid-20th century.
The province was officially formed on October 15, 1963, through the separation of land from the provinces of Long An, Bình Dương, and Tây Ninh. Its capital city was Khiêm Cường.
Hậu Nghĩa was divided into four distinct districts: Củ Chi, Đức Hòa, Đức Huệ, and Trảng Bàng.