Greenville is a town in Piscataquis County, Maine, United States. The population was 1,623 at the 2000 census. The town is centered around the lower end of Moosehead Lake, the largest body of fresh water in the state. Greenville is the historic gateway to the north country and a center for outdoor recreation in the area. Little Squaw Public Reserved Land and Lily Bay State Park are located nearby, in neighboring Moosehead Junction Township and Beaver Cove, respectively.