Cornelis de Graeff (23 August 1671, Amsterdam – 16 February 1719, Ilpendam) was a member of the family De Graeff, a prominent regent family from the Dutch Golden Age.His parents were Pieter de Graeff and Jacoba Bicker, his younger brother was Johan de Graeff, the Lord of the semisouverain Lordship Zuid-Polsbroek. Cornelis never married.Cornelis de Graeff was a Canon of St. Pieter at Utrecht. Most of the time he resided at his castle Ilpenstein.