Sewell Anton Peterson (February 28, 1850 – September 20, 1915) was an American politician.

Born in Norway, he settled in Wisconsin in 1861. He was the son of Ole and Martha Peterson. He lived in Menomonie, Wisconsin, where he was a merchant. During that time, Peterson served on the Menomonie Common Council. Then he moved to Rice Lake, Wisconsin, where he served as city clerk, city treasurer, and mayor. In 1893, he served in the Wisconsin State Assembly. From 1895 to 1899, he served as the Wisconsin State Treasurer. He was an alternate delegate to Republican National Convention from Wisconsin in 1900.^[1] He died in Rice Lake in 1915 after accidentally shooting himself in the stomach while hunting. He was buried at the Nora Cemetery in Rice Lake, Wisconsin.^[2]