Nicola Michetti, also known as Niccolo or Niccolò was an Italian architect, active in a late-Baroque style in mostly Rome, Italy and St Petersburg, Russia.
While born in Venice, Nicola worked for years in Rome under Carlo Fontana, including as a foreman in the reconstruction of the Basilica of Santi Apostoli. Nicola independently submitted a proposal for the Trevi Fountain, however, the winning commission went to Salvi. Nicola performed smaller architectural projects in Rome, including the altar and the architecture of the Sacripante chapel in Sant'Ignazio. In 1715, he submitted a losing design against competitors like Juvarra, Canevari and others to be able to design a new sacristy of St. Peter's Basilica. That same year, he designed and help build a chapel of the church of Santa Maria in Transpontina and for the Rospigliosi chapel in the church of San Francesco a Ripa.
Between 1718 and 1723, Michetti moved to Russia, and became employed by Tsar Peter the Great as court architect. His main work of these years is the garden and the cascading fountain of the Peterhof Palace near St Petersburg. He made designs for the Kadriorg Palace in Tallinn and the Constantine Palace in Strelna.