| Birth Name: | Cosmin Aurel Rațiu |
| Birth Date: | 18 July 1979 |
| Birth Place: | Petroșani, Romania |
| Weight: | 260lbs |
| Ru Position: | Flanker, Lock |
| Years1: | – |
| Clubs1: | Știința Petroșani |
| Years2: | – |
| Clubs2: | CSRTM Callatis Mangalia |
| Years3: | – |
| Clubs3: | Dinamo București |
| Years4: | 2006–07 |
| Clubs4: | Stade Montois |
| Years5: | 2013–14 |
| Clubs5: | Dinamo București |
| Apps5: | 3 |
| Points5: | 0 |
| Years6: | 2013–14 |
| Clubs6: | Farul Constanța |
| Apps6: | 3 |
| Points6: | 0 |
| Years7: | 2014–15 |
| Apps7: | 9 |
| Points7: | 15 |
| Years8: | 2015–16 |
| Clubs8: | Steaua București |
| Years9: | 2016–18 |
| Clubs9: | Politehnica Iași |
| Apps9: | 9 |
| Points9: | 5 |
| Ru Province1: | București Wolves |
| Ru Provinceyears1: | 2005–12 |
| Ru Provinceapps1: | 24 |
| Ru Provincepoints1: | 10 |
| Ru Provinceupdate: | 28 March 2020 |
| Repyears1: | 2003–2011 |
| Repcaps1: | 34 |
| Reppoints1: | 10 |
| Coachyears1: | 2016–18 |
| Coachteams1: | Politehnica Iași |
Cosmin Aurel Rațiu (born 18 July 1979 in Petrosani) is a retired Romanian rugby union player. He also played as a lock or flanker. He is currently a coach.[1]
He played for CS Dinamo București until moving to Stade Montois in France for the 2006–07 season. He currently plays for Politehnica Iași in the SuperLiga.
He gathered 34 caps for Romania, having made his debut in 2003 against the Czech Republic. He has scored 2 tries, 10 points overall. He played at the 2007 Rugby World Cup and played all four games, three of them as a substitute. He also played at the 2011 Rugby World Cup.