| Constantin Grecu | |
| Height: | 1.82m (05.97feet) |
| Birth Date: | 1988 6, df=yes |
| Birth Place: | Craiova, România |
| Position: | Left back |
| Youthyears1: | 1995–2007 |
| Youthclubs1: | Școala de Fotbal Gheorghe Popescu |
| Years1: | 2007 |
| Clubs1: | Energia Rovinari |
| Caps1: | ? |
| Goals1: | ? |
| Years2: | 2008–2011 |
| Clubs2: | Pandurii Târgu Jiu |
| Caps2: | 64 |
| Goals2: | 0 |
| Years3: | 2008 |
| Clubs3: | → Râmnicu Vâlcea (loan) |
| Caps3: | 17 |
| Goals3: | 1 |
| Years4: | 2011–2012 |
| Clubs4: | Universitatea Cluj |
| Caps4: | 14 |
| Goals4: | 0 |
| Years5: | 2012–2013 |
| Clubs5: | Petrolul Ploiești |
| Caps5: | 3 |
| Goals5: | 0 |
| Years6: | 2013–2014 |
| Clubs6: | Dinamo București |
| Caps6: | 24 |
| Goals6: | 0 |
| Years7: | 2015–2016 |
| Clubs7: | Pandurii Târgu Jiu |
| Caps7: | 29 |
| Goals7: | 0 |
| Years8: | 2017 |
| Clubs8: | Sepsi OSK |
| Caps8: | 15 |
| Goals8: | 0 |
| Years9: | 2018–2020 |
| Clubs9: | FC U Craiova |
| Caps9: | 11 |
| Goals9: | 0 |
| Years10: | 2020–2021 |
| Clubs10: | Pandurii Târgu Jiu |
| Caps10: | 10 |
| Goals10: | 0 |
| Totalcaps: | 156 |
| Totalgoals: | 1 |
| Nationalyears1: | 2004 |
| Nationalteam1: | Romania U–17 |
| Nationalcaps1: | 4 |
| Nationalgoals1: | 0 |
| Nationalyears2: | 2007 |
| Nationalteam2: | Romania U–21 |
| Nationalcaps2: | 1 |
| Nationalgoals2: | 0 |
| Nationalyears3: | 2012–2014 |
| Nationalteam3: | Romania |
| Nationalcaps3: | 1 |
| Nationalgoals3: | 0 |
| Pcupdate: | 1 March 2021 |
Constantin Grecu (born 8 June 1988) is a Romanian footballer who plays as a left back.