Mathias Dahl (January 6, 1884 – August 3, 1976) was a North Dakota politician who was well known for his tenure as the North Dakota Commissioner of Agriculture and Labor from 1939 to 1964. His long tenure in the office ended a period of instability in the department when the three previous commissioners only served one two-year term. He re-elected a total of twelve times, and was one of the most prominent Republican/Non-Partisan League (NPL) politicians in the state.