The park covers over , and is dominated by Acacia-Commiphora vegetation; it is contiguous with Kenya's Tsavo West National Park. The area commonly called 'Mkomazi' is actually the union of two previous game reserves, the Umba Game Reserve in the east (in Lushoto District, Tanga Region) and the Mkomazi Game Reserve in the west (in Same District, Kilimanjaro Region); in government documents they are sometimes called the Mkomazi-Umba Game Reserves.
The park covers over , with Acacia-Commiphora vegetation dominating its landscape. It is contiguous with Kenya's Tsavo West National Park and comprises two former game reserves: Umba Game Reserve (in Lushoto District, Tanga Region) and Mkomazi Game Reserve (in Same District, Kilimanjaro Region). These are sometimes referred to as the Mkomazi-Umba Game Reserves in official documents.