Mark Aubrey Tennyson, 5th Baron Tennyson DSC (28 March 1920 – 3 July 2006) was a British peer. He was the second son of Lionel Tennyson, 3rd Baron Tennyson and the Hon. Clarissa Madeline Georgiana Felicite Tennant. The great-grandson of poet Alfred, Lord Tennyson, he succeeded his brother as 5th Baron Tennyson in 1991.