Lady Agnew of Lochnaw is an oil on canvas painting by the American portrait artist John Singer Sargent. Commissioned in 1892 by Sir Andrew Agnew, 9th Baronet of Lochnaw Castle in Wigtownshire. The subject being his wife, Gertrude Agnew whom he loved dearly. Bequeathed through the Cowan Smith Bequest Fund in 1925, it is now owned & exhibited by the Scottish National Gallery in Edinburgh, Scotland.