The Jewett Piano Company Building is an historic building at 140 Adams Street in Leominster, Massachusetts. Built in 1892, it is a well-preserved example of late 19th-century wood-frame industrial construction. It is one of two surviving 19th-century piano case company plants in the city, which was known for this industry until World War I. The building was listed on the National Register of Historic Places in 2019. The building has been converted to residential use, known as Ivory Key Apartments.