Hazen is a city in Mercer County, North Dakota in the United States. The population was 2,457 at the 2000 census. Hazen was founded in 1913. Hazen has a K-12 school system. Because of its proximity to Beulah, a town of similar size about 10 km (5 mi) away, Hazen is rarely mentioned by itself but rather as Hazen-Beulah. It is located about a half an hour away from the largest lake in North Dakota.