Harrisville is a village in Lewis County, New York, United States. The population was 628 at the 2010 census.The Village of Harrisville is in the northeast part of the Town of Diana and is south of Ogdensburg.Harrisville is located at 44°09′08″N 75°19′11″W / 44.152226°N 75.319733°W / 44.152226; -75.319733.According to the United States Census Bureau, the village has a total area of 0.8 square miles, of which, 0.8 square miles of it is land and 0.04 square miles of it is water.Combined New York State Route 812 and New York State Route 3 pass through the community. County Road 9 enters the village from the south.Harrisville is on a branch of the Oswegatchie River and is next to the county line for St. Lawrence County.As of the census of 2000, there were 653 people, 266 households, and 172 families residing in the village. The population density was 849.6 people per square mile. There were 299 housing units at an average density of 389.0 per square mile.