Nyanza Province (Kenyan English: [ˈɲaːnzə]; Swahili: Mkoa wa Nyanza) was one of Kenya's eight administrative provinces before the formation of the 47 counties under the 2010 constitution.

The region is located in the southwestern part of Kenya around Lake Victoria.

There are also Bantu-speaking tribes, such as the Kuria, and some Luhya, living in the province.

The province derives its name from Nyanza, a Bantu word which means a large mass of water.

The provincial capital was Kisumu, the third-largest city in Kenya.