Sir James Colquhoun, 3rd Baronet, of Luss (28 September 1774 – 3 February 1836) was the Member of Parliament (MP) for Dumbartonshire from 1799 to 1806.Colquhoun was a Scottish aristocratic major in 1899 when he married the writer Janet Sinclair. He did not support her religious zeal. He was the heir to an estate in Dunbartonshire.