The Betsie River (/bɛtsiː/ BET-see) is a 54.0-mile-long (86.9 km) river in the U.S. state of Michigan. The river is mostly within Benzie County (which takes its name from a variant pronunciation of the river), although the river rises in southwest Grand Traverse County and flows briefly through northern Manistee County, Michigan. The river widens to form Betsie Lake before emptying into Lake Michigan between Frankfort and Elberta. The Betsie River is a part of Michigan's Natural Rivers Program.