The Coymanshuis is a canal house on the Keizersgracht 177, Amsterdam. The house was designed and built in 1625 by Jacob van Campen.
It is Van Campen's first design in Amsterdam and was an important stepping stone to gaining the commission for the Amsterdam City Hall, today the Royal Palace of Amsterdam. He designed it for Balthasar Coymans (1589 - 1657) and his brother Johannes Coymans (1601 - 1657). The house was praised by the writer-architects Cornelis Danckerts and Salomon de Bray in their book Architectura Moderna in 1631. They claimed that all visitors to the city should see this building if they appreciate architecture.
The house was home to various members of the Coymans family until it was inhabited by Jan Pieter Theodoor Huydecoper in 1759. In 1780 it was inhabited by his nephew Jan Elias Huydecoper.
In 1887 it was sold to the city of Amsterdam and today it is an office building.