Ralph de Cromwell, 3rd Baron Cromwell (c. 1393 – January 4, 1456) is an English politician and diplomat.

A Privy Councillor from 1422, he serves as Treasurer of England (1433–1443) and twice as Chamberlain of the Household (1425–1432 and 1450–1455) during the reign of Henry VI.

He also owns and develops a number of properties, including Tattershall Castle in Lincolnshire.