Webb Granite Quarry, also known as Marlboro Quarry, was a granite quarry located in Marlborough. It was operated by Webb Granite and Construction Company from 1849 to 1930. The quarry produced high-quality granite that was used for buildings and monuments, such as the First Church of Christ, Scientist in Boston, Massachusetts. The quarry was connected to Webb station by a 4-mile siding that facilitated the transportation of the granite blocks. The quarry was abandoned in the 1930s.

Webb Granite Quarry is on the north side of Jaffrey Road (NH-124).