Willo is a given name. Notable people with the name include:
Willo Davis Roberts (1928–2004), American writer of children's novels Willo Flood (born 1985), Irish footballer Willo McDonagh (born 1983), Irish footballer
See also Willo the Wisp, British cartoon series originally produced in 1981 Willo, a specimen of the dinosaur Thescelosaurus falsely thought to have had a fossilised heart.