Williamson, who is from Welcome, Minn., was 4-1 with one save during his freshman season with the Trojans in 2017. He had 47 strikeouts with 25 walks and a 3.86 earned run average.
Williamson, who is 6 feet, 5 inches and 205 pounds, is the second NIACC player to verbally commit to a NCAA Division I school this fall. Sophomore first baseman Bryce Ball committed to Dallas Baptist University in September.
Michigan State was 29-23 overall and 10-14 in the Big Ten Conference in 2017.