Christof Marselis (1670s – 1731) was a Polish-Dutch architect who worked in several European countries, including Denmark and Russia.
Christof Marselis was born in Poland some time in the 1670s. He lost his parents at an early age and worked in the household of John III Sobieski in Warsaw before studying architecture and working as an architect in the Netherlands. He later continued to Italy to further his studies.
In c. 1702 he travelled to Copenhagen, Denmark, where he worked as royal architect under Wilhelm Friedrich von Platen. The exact extent of his contributions remain uncertain but he worked on such buildings as the Garrison Church (1703–06), the Stable Master's House (1703–05) and Frederiksberg Palace in Copenhagen.
In about 1716 he left Denmark and worked his way through Germany and Poland before ending up in Russia, where he designed mansions in both Saint Petersburg and Moscow. He also made a design for a cathedral in Moscow which was never built.