Charndon is a hamlet in the parish of Twyford, in Buckinghamshire, England.

The hamlet name has a mixture of Celtic and Anglo Saxon origins, as is common with other places in this part of the country (see, for example, Brill and Bow Brickhill). It means 'cairn hill', cairn being a Celtic word for a ceremonial hill or pile of stones. The hamlet was recorded in the Domesday Book in 1086 as Credendone.

Situated within the hamlet of Charndon is the estate of Charndon Grounds, once a large stately home.