Hector Guimard (March 10, 1867 – May 20, 1942) is a French architect, who is now the best-known representative of the Art Nouveau style of the late nineteenth and early twentieth centuries.

Guimard's critical reputation has risen since the 1960s, as many art historians have praised his architectural and decorative work, the best of it done during a relatively brief fifteen years of prolific creative activity.