Monomeith is a locality in Victoria, Australia, south-east of Melbourne's central business district, located within the Shire of Cardinia local government area. Monomeith recorded a population of 69 at the 2021 census.
In 1942, during World War II, a military airfield was constructed for the air defence of Melbourne, south of Spencers Road, and is still visible using Google Earth.
The word Monomeeth is a Boonwurrung word meaning "good."
Monomeith Post Office opened on 20 July 1900 and closed in 1969.
A railway station existed from 1890 until the late 1970s.
The site of the former airfield has been considered, as of 2015, as a site for Melbourne's third major airport for passenger jet aircraft.