Girardeau is a French surname. Notable people with the surname include:
Émile Girardeau (1882–1970), French engineer
John Girardeau (1825–1898), American Presbyterian minister and theologian
Marvin D. Girardeau, quantum physicist, currently a research professor at the University of Arizona
W. L. Girardeau, trustee of Stanton College Preparatory School
Isabella Girardeau, opera soprano in the 1711 premiere of Rinaldo
Frank Girardeau, actor who had a guest appearance on Law & Order: Criminal Intent episode "No Exit"
