Thatcher Magoun (June 17, 1775 – April 16, 1856)[1] was a shipbuilder who specialized in large ships and brigs, 250-tons and larger, built for the China trade.

In 1803, Magoun established the first shipyard in Medford, Massachusetts on what is known today as Riverside Avenue, opposite the end of Park Street.

He specialized in big ships and brigs, which were 250-tons and larger in size, built for Old China Trade.

According to the maritime historian Admiral Samuel Eliot Morison, Magoun's reputation was "second to none among American shipbuilders.

Magoun built a mansion on High Street, Medford, Massachusetts which eventually became the town library.