Franz Christian Gau (15 June 1790, in Cologne – January 1854, in Paris) was a French architect and archaeologist of German descent.
In 1809 he entered the Académie des Beaux-Arts, Paris, and in 1815 visited Italy and Sicily.
It consists of sixty-eight plates, of plans, sections, and views, and was received as an authority.
He directed the restoration of the churches of Saint-Julien-le-Pauvre, and Saint-Séverin, and built the great prison of La Roquette, etc.
Illness compelled him to relinquish the care of supervising the work, and he died before its completion.