Muniz or Muñiz is a surname, primarily in the Spanish language, where it is spelled Muñiz (Muniz is an American or Portuguese variant). It may refer to:
Aned Y. Muñiz Gracia, a professor
Carlos Muñiz (born 1981), a baseball player
Frankie Muniz (born 1985), an American actor
Júlio César de Paula Muniz Júnior (born 1988), a Brazilian football player
Manny Muñiz (born 1947), a Puerto Rican baseball player
Marco Antonio Muñiz (born 1933), a Mexican singer
Marc Anthony (born 1968), a Puerto Rican singer (born Marco Antonio Muñiz) Rafo Muñiz (born 1956), a Puerto Rican actor, director, & producer Tomás Muñiz (1900-1965), a Puerto Rican radio and television producer Tommy Muñiz (1922-2009), a Puerto Rican comedian Vik Muniz (born 1961), an avant-garde artist