Moniz is a surname in the Portuguese language, namely in Portugal and Brazil. It may refer to:
- António Egas Moniz (1874-1955), Portuguese physician, neurologist and Nobel Prize laureate
- Bryant Moniz, quarterback for the University of Hawaii Warriors football team
- Charlie Moniz (born 1980), Canadian musician
- Diogo Gil Moniz, Portuguese nobleman, son of Gil Aires Moniz
- Febo Moniz (1515-aft. 1580), Portuguese nobleman
- Febo Moniz de Lusignan, Portuguese nobleman, grandfather of Febo Moniz
- Felipa Perestrello Moniz, Portuguese wife of Christopher Columbus
- Frank Moniz (1911-2004), American soccer player
- Gil Aires Moniz, Portuguese nobleman
- Jeffrey Moniz (born 1969), American professor
- Júlio Botelho Moniz (1900-1970), Portuguese soldier and politician
- Lúcia Moniz (born 1976), Portuguese singer and actress
- Martim Moniz (died 1147), Portuguese knight noted for his role in the Siege of Lisbon
- Pedro Moniz da Silva, Portuguese nobleman, son of Diogo Gil Moniz
- Ricardo Moniz (born 1964), Dutch former footballer and current coach of FC Red Bull Salzburg
- Rui Gil Moniz, Portuguese nobleman, son of Gil Aires Moniz
- Vasco Gil Moniz (died 1497), Portuguese nobleman, son of Gil Aires Moniz
- Wendy Moniz (born 1969), American actress