Constantine is a village in St. Joseph County in the U.S. state of Michigan. The population was 2,076 at the 2010 census. The village is located within Constantine Township. U.S. Highway 131 (Main Street in the village) leads to Kalamazoo to the north and to the Indiana Toll Road six miles to the south. The St. Joseph River, navigable from source to outlet, passes through the village, emptying in Lake Michigan to the west.