Erwin Library and Pratt House is a historic library building and house located in Boonville in Oneida County, New York. The library building was built in 1890 of rock-faced local limestone with a square tower at the entrance. The Pratt House was constructed in 1875. It is of brick with a foundation of smooth limestone and a mansard roof with a central tower. It was listed on the National Register of Historic Places in 1973.