The Edmund Dwight House is a historic house at 5 Cambridge Street in Winchester, Massachusetts, straddling the town line with Arlington. It was built in 1858 in an Italianate style. It was one of the first and grandest country houses built in Winchester at a time when Boston businessmen were seeking to build such houses. Edmund Dwight, the wealthy businessman who was its first owner, was married to a great-granddaughter of Thomas Jefferson. The house's design is believed to be based loosely on that of Jefferson's Monticello. The house is sited for an expansive view of the Upper Mystic Lake.
Significant alterations were made to the house in the 1890s, including the stuccoing of the exterior, and the addition of a two story ell to the northeast corner. These changes were made under the auspices of local architect Robert Coit. A second, single-story, addition was made to the northwest corner in 1985.