Guillermo Diaz may refer to:
Guillermo Díaz-Plaja (1909–1984), Spanish literary critic, historian and poet. Guillermo Díaz (footballer, born 1926), Chilean footballer Guillermo Díaz (footballer, born 1930) (1930–1997), Chilean footballer Guillermo Díaz Gea (born 1944), Mexican politician Guillermo Díaz (wrestler) (born 1964), Mexican Olympic wrestler Guillermo Díaz (actor) (born 1975), American actor Guillermo Díaz (footballer, born 1979), Uruguayan footballer Guillermo Diaz (basketball) (born 1985), Puerto Rican basketball player Guillermo Díaz (footballer, born 1994), Chilean footballer Memo Diaz, (born 1995), American soccer player