The Clinton County Courthouse Complex is a historic county government and courthouse site located at 135 Margaret Street in Plattsburgh, Clinton County, New York. The main courthouse was constructed in 1889. It is a two-story, ashlar stone and brick Richardsonian Romanesque style building. It has a hipped roof and rock-faced arched openings. It features a large, square central tower with an open campanile and pyramidal roof. The associated Surrogate's Building was built in 1884–1885, and is a two-story, Italianate style brick building with a bracketed cornice with Renaissance style detail. The courthouse complex was added to the National Register of Historic Places on November 12, 1982.