Matthew Newcomen (c. 1610 – 1 September 1669) was an English nonconformist churchman. His exact date of birth is unknown. He was educated at St John's College, Cambridge (M.A. 1633). In 1636 he became lecturer at Dedham in Essex, and led the church reform party in that county. He assisted Edmund Calamy the Elder in writing Smectymnuus (1641), and preached before parliament in 1643. He was multi-talented, excelling in preaching and debate, and was offered several lucrative positions.