Ian Ormiston Davidson (born 1 January 1951) is a former Member of the South African Parliament from the Democratic Alliance.

After matriculating from Parktown Boys' High School, Davidson went to the University of the Witwatersrand where he studied law.

Davidson served in the Gauteng Provincial Legislature from 1994 to 1999 and was first elected to parliament in 1999.

[2] In May 2007 he became the chief whip of the party in parliament,[3] taking over from Douglas Gibson.

He also served on the portfolio committee on finance, representing the constituency of Linden, Johannesburg.