Mwanza, city, northern Tanzania, capital of Mwanza Region, a port on Lake Victoria. The city handles much of Tanzania's lake trade with Kenya and Uganda and is an administrative center for the northwest. Chief industries include cotton-textile manufacturing, meat packing, and fishing. A railroad connects with Dodoma and Dar es Salaam. The East African Institute for Medical Research (1949) is here. Population (1988) 233,013.