Hazen is a city in Mercer County, North Dakota, United States.

[8] The Fred Krause House, now on the National Register of Historic Places, was built in 1916.

According to the United States Census Bureau, the city has a total area of 1.27 square miles (3.29 km2), all land.

There were 1,074 housing units at an average density of 845.7 per square mile (326.5/km2).

24.6% of all households were made up of individuals, and 9.1% had someone living alone who was 65 years of age or older.

There were 1,131 housing units at an average density of 912.2 per square mile (352.2/km2).

The top 6 ancestry groups in the city are German (71.7%), Norwegian (18.4%), Russian (9.4%), Irish (8.8%), English (6.0%), Swedish (4.0%).

25.0% of all households were made up of individuals, and 11.4% had someone living alone who was 65 years of age or older.