Sir Colin Norman Thornton-Kemsley, OBE, TD (2 September 1903 – 17 July 1977) was a Conservative and National Liberal politician in the United Kingdom.

He also served as the Honorary Treasurer of Essex and Middlesex Provincial Area, National Union of Conservative and Unionist Associations.

In 1939 Malcolm Barclay-Harvey, the incumbent Unionist Member of Parliament for Kincardine and Western Aberdeenshire, was offered the position of Governor of South Australia.

Thornton-Kemsley, due to his previous role in trying to bringing about a deselection of Churchill by the Epping Conservative Association, was offered the candidacy.

Churchill's reply was characteristic: "I certainly think that Englishmen ought to start fair with one another from the outset in so grievous a struggle, and so far as I am concerned the past is dead."