Nelson Welsh Congregational Church is a historic Congregational church located at Nelson, Madison County, New York. It was built in 1876, and is a one-story, three bay by four bay, timber frame structure with a gable roof and stone foundation. It measures 34 feet by 55 feet. It features a three-stage bell tower with octagonal spire. Also on the property are a contributing privy and cemetery. The cemetery contains the graves of Nelson's earliest settlers with the oldest stone dated to 1809.