Henry Meysey Meysey-Thompson, 1st Baron Knaresborough (30 August 1845 – 3 March 1929) was a Liberal (and later Liberal Unionist) politician who sat in the House of Commons variously between 1880 and 1905 when he was raised to the peerage as Baron Knaresborough.
Meysey-Thompson was born at Kirby Hall, near Great Ouseburn, North Yorkshire, the son of Sir Harry Meysey-Thompson, 1st Baronet and his wife Elizabeth Anne Croft, daughter of Sir John Croft, 1st Baronet. He was educated at Eton College and at Trinity College, Cambridge where he won his blue in athletics and was awarded BA in 1868. He became a private secretary to William Ewart Gladstone. In 1874, he succeeded to the Meysey-Thompson baronetcy which had been created for his father less than two months earlier. He was a J.P. for the North and West Ridings of Yorkshire, and captain in the Yorkshire Hussars Yeoman Cavalry.
At the 1880 general election Meysey-Thompson was elected Liberal Member of Parliament (MP) for Knaresborough, but his election was declared void on 23 July 1880. In 1885 he stood for parliament unsuccessfully at North Lincolnshire. At the 1885 general election he was elected MP for Brigg. However, in 1886, as one of the MPs who opposed Gladstone's Irish Home Rule Bill, he joined the breakaway Liberal Unionist Party, but was not re-elected.