Major Ronald Owen Lloyd Armstrong-Jones, MBE QC DL (né Jones; 18 May 1899 – 27 January 1966) was a British barrister and soldier.

He was the father of Antony Armstrong-Jones, 1st Earl of Snowdon, and father-in-law of Princess Margaret, younger daughter of George VI.

In 1912, his father legally changed the family surname to Armstrong-Jones by deed poll to distinguish himself from another Robert Jones.

[8] While at Oxford he distinguished himself as a rower, helping the Magdalen crew to win the Grand Challenge Cup at Henley in 1921.

[10] During the Second World War he returned to the army and served as a Major in the King's Royal Rifle Corps; he was invalided out in 1945, after serving as Deputy Judge Advocate to Montgomery's staff in Normandy and being appointed a Member of the Order of the British Empire in the 1945 New Year Honours in recognition of his service.

On 18 June 1936, Armstrong-Jones married secondly Australian Carol Akhurst, daughter of Sir Thomas Melrose Coombe.