Mohave County is located in the northwestern corner of the U.S. state of Arizona. As of the 2010 census, its population was 200,186, an increase of 45,154 people since the 2000 census count of 155,032. The county seat is Kingman. While the largest single city is Lake Havasu City, the area with highest population is the Bullhead City/Fort Mohave/Mohave Valley area.

Mohave County contains parts of Grand Canyon National Park and Lake Mead National Recreation Area and all of the Grand Canyon-Parashant National Monument. The Kaibab, Fort Mojave and Hualapai Indian Reservations also lie within the county.

Mohave County is the fifth-largest county in the United States by land area.