| Club: | Lens |
| Season: | 2003–04 |
| Chrtitle: | President |
| Chairman: | Gervais Martel |
| Mgrtitle: | Head coach |
| Manager: | Joël Müller |
| Stadium: | Stade Bollaert-Delelis |
| League: | Ligue 1 |
| League Result: | 8th |
| Cup1: | Coupe de France |
| Cup1 Result: | Round of 32 |
| Cup2: | Coupe de la Ligue |
| Cup2 Result: | Second round |
| Cup3: | UEFA Cup |
| Cup3 Result: | Second round |
| Prevseason: | 2002–03 |
| Nextseason: | 2004–05 |
The 2003–04 season was the 105th season in RC Lens's history. The club participated in the Ligue 1, the Coupe de France, Coupe de la Ligue and UEFA Cup. The season began on 2 August 2003 and concluded on 23 May 2004.
Source:[1]
|-! colspan="14" style="background:#dcdcdc; text-align:center"| Goalkeepers|-! colspan="14" style="background:#dcdcdc; text-align:center"| Defenders|-! colspan="14" style="background:#dcdcdc; text-align:center"| Midfielders|-! colspan="14" style="background:#dcdcdc; text-align:center"| Forwards|-