Viliamu is a masculine given name. Notable people with the name include:

Viliamu Afatia (born 1990), Samoan rugby union player Viliamu Lesiva (born 1965), Samoan boxer

See also Viliam Kyngstonn Viliamu-Asa, American football player Narita Viliamu Tahega (born 1989), Niuean weightlifter