C. B. Fisk, Inc. is a company in Gloucester in the U.S. state of Massachusetts that designs and builds mechanical action pipe organs. It was founded in Gloucester in 1960 by Charles Brenton Fisk (1925–1983) and Thomas W. Byers.

Charles Brenton Fisk was an American pipe organ builder. He was one of the first to use mechanical tracker actions instead of electro-pneumatic actions in modern organ construction. Originally involved in the Manhattan Project, Fisk made a career change from atomic physics to organ building. He later co-founded C.B. Fisk, Inc., an organ building firm.