Hải Hưng (pronounced "high-hung") is a former province in the Red River Delta of Vietnam.

Hải Hưng had one town (Hưng Yên), and ten districts: Chí Linh, Kim Môn, Nam Thanh, Cẩm Bình, Tứ Lộc, Ninh Thanh, Mỹ Văn, Châu Giang, Kim Thi and Phù Tiên.

When merging, the province has two towns—Hai Duong town (the provincial capital) and Hung Yen town—and 20 districts: Ân Thi, Bình Giang, Cẩm Giàng, Chí Linh, Gia Lộc, Khoái Châu, Kim Động, Kim Thành, Kinh Môn, Mỹ Hào, Nam Sách, Ninh Giang, Phù Cừ, Thanh Hà, Thanh Miện, Tiên Lữ, Tứ Kỳ, Văn Giang, Văn Lâm, and Yên Mỹ.

Thus, the administrative unit of the province by the beginning of 1996 includes Hai Duong town (the provincial capital), Hung Yen town, 10 districts: Cam Binh, Chau Giang, Chi Linh, Kim Mon, Kim Thi, My Van, Nam Thanh, Ninh Thanh, Phu Tien, Tu Loc.

By the end of 1996, the administrative units of the province include Hai Duong town (the provincial capital), Hung Yen town and 13 districts: An Thi, Cam Binh, Chau Giang, Chi Linh, Gia Loc, Kim Động, Kim Mon, My Van, Nam Thanh, Ninh Giang, Phu Tien, Thanh Mien, Tu Ky. On November 6, 1996, the 10th session of the IXth National Assembly issued a resolution to divide Hai Hung province to re-establish Hai Duong and Hung Yen provinces.