Hallam Tennyson, 2nd Baron Tennyson, (11 August 1852 – 2 December 1928) was a British aristocrat who served as the second governor-general of Australia, in office from 1903 to 1904. He was previously Governor of South Australia from 1899 to 1902.

Tennyson was born in Twickenham, Middlesex, and educated at Marlborough College and Trinity College, Cambridge. He was the eldest son of the poet Alfred, Lord Tennyson, and served as his personal secretary and biographer; he succeeded to his father's title in 1892. Tennyson was made Governor of South Australia in 1899. When Lord Hopetoun resigned the governor-generalship in mid-1902, Tennyson was the longest-serving state governor and thus became Administrator of the Government. Tennyson was eventually chosen to be Hopetoun's permanent replacement, but accepted only a one-year term. He was more popular than his predecessor among the general public, but had a tense relationship with Prime Minister Alfred Deakin and was not offered an extension to his term. Tennyson retired to the Isle of Wight, and spent the rest of his life upholding his father's legacy.