Martin Nelson Johnson (March 3, 1850 – October 21, 1909) was an American attorney and politician who served as a United States representative and senator from North Dakota.

Born to Norwegian immigrants in Racine County, Wisconsin in 1850, he moved with his parents to Decorah, Iowa in the same year.

They purchased 2,500 acres near the Great Northern Railway a few miles west of Larimore, North Dakota.

He was district attorney of Nelson County from 1886 to 1890, and was a member of the constitutional convention of North Dakota in 1889, where he gained attention for his support of a unicameral state legislature.

Feeling like they had found a strong voice, Norwegian farmers across North Dakota fought to get Johnson on the ballot for the U.S. Senate.

[4] Johnson died on October 21, 1909, in the Gardner Hotel in Fargo, North Dakota after an attack of Bright's disease following nasal surgery.