Morrisonville is a hamlet and census-designated place in Clinton County, New York, United States. The population was 1,545 at the 2010 census.Morrisonville is divided between the towns of Plattsburgh and Schuyler Falls by the Saranac River, which defines the boundary between the two towns. The community is west of the city of Plattsburgh.Morrisonville is located 5 miles west of downtown Plattsburgh at 44°41′27″N 73°33′3″W / 44.69083°N 73.55083°W / 44.69083; -73.55083. New York State Route 22B passes through the village, beginning at New York State Route 3 near the eastern end of the CDP and leading south to the hamlets of Schuyler Falls and Peru.According to the United States Census Bureau, the Morrisonville CDP has a total area of 2.7 square miles, of which 2.6 square miles is land and 0.08 square miles, or 3.35%, is water.In the census of 2000, there were 1,702 people, 648 households, and 463 families residing in the CDP. The population density was 658.3 per square mile.