Desmond Joseph O'Brien (22 May 1919 — 26 December 2005) was an Irish rugby union international.
O'Brien, born in Dublin and educated at Belvedere College, was a back-row forward.
[1] A Leinster representative player, O'Brien was capped 20 times for Ireland.
Debuting as a 28-year old in 1948, he played three of four Tests in that year's Five Nations Championship, with Ireland achieving the grand slam.
[3] Since the 1960s, O'Brien lived in the Edinburgh area and held executive roles in the brewery industry.