Loiseau is a French surname, most prevalent in Loiret. Notable people with the surname include:
Gustave Loiseau (1865–1935), French painter Carlos Loiseau (1948–2012), Argentine cartoonist Dominique Loiseau (1949–2013), French and Swiss watchmaker Bernard Loiseau (1951–2003), French chef Annick Loiseau (born 1957), French physicist Philippe Loiseau (born 1957), French politician Patrick Loiseau (born 1960), French politician Nathalie Loiseau (born 1964), French diplomat and academic administrator Hervé Djamel Loiseau (born 1973), French soldier David Loiseau (born 1979), Haitian-Canadian mixed martial arts fighter Shawn Loiseau (born 1989), American footballer