Ninnis may refer to:
Ninnis Glacier Mertz-Ninnis Valley Belgrave Edward Sutton Ninnis (1887–1912), British Army officer and Antarctic explorer Belgrave Ninnis (1837–1922), Royal Navy surgeon, pioneer of Northern Australia, surveyor, Arctic explorer, and Freemason Scott Ninnis (born 1965), Australian basketball player
See also Ninni, a given name