Gainesville is a village in Wyoming County, New York, United States.

According to the United States Census Bureau, the village has a total area of 0.9 square mile (2.2 km2), all land.

As of the census of 2000, there were 304 people, 113 households, and 87 families residing in the village.

16.8% of all households were made up of individuals, and 4.4% had someone living alone who was 65 years of age or older.

Out of the total people living in poverty, 6.7% are under the age of 18 and 0.0% are 65 or older.