| Club: | Rennes |
| Season: | 2015–16 |
| Manager: | Philippe Montanier |
| Chairman: | René Ruello |
| Stadium: | Roazhon Park |
| League: | Ligue 1 |
| League Result: | 8th |
| Cup1: | Coupe de France |
| Cup1 Result: | Round of 32 |
| Cup2: | Coupe de la Ligue |
| Cup2 Result: | Round of 16 |
| League Topscorer: | Ousmane Dembélé (12) |
| Season Topscorer: | Ousmane Dembélé (12) |
| Highest Attendance: | 29,060 vs Nantes (6 March 2016) |
| Lowest Attendance: | 9,595 vs FBBP 01 (19 January 2016) |
| Prevseason: | 2014–15 |
| Nextseason: | 2016–17 |
| Website: | http://www.staderennais.com/ |
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The 2015–16 Stade Rennais season was the 115th professional season of the club since its creation in 1901.
French teams are limited to four players without EU citizenship. Hence, the squad list includes only the principal nationality of each player; several non-European players on the squad have dual citizenship with an EU country. Also, players from the ACP countries—countries in Africa, the Caribbean, and the Pacific that are signatories to the Cotonou Agreement—are not counted against non-EU quotas due to the Kolpak ruling.
.[1]
| Date | Player | Moved from | Fee | Notes | |||
|---|---|---|---|---|---|---|---|
 Lens | Free Transfer | ||||||
 | Basel | Undisclosed | |||||
 | Aston Villa | Undisclosed | [2] | ||||
| Pedro Mendes |  Parma | Free Transfer | |||||
| Lyon | Undisclosed | ||||||
| | Unattached | Free Transfer | |||||
 | Orlando Pirates | Undisclosed | [3] |
| Date | Player | Loaned from | On loan until | Notes | |||
|---|---|---|---|---|---|---|---|
| | Chelsea | 30 June 2016 | |||||
 | Porto | 30 June 2016 |
| Date | Player | Moved to | Fee | Notes | |||
|---|---|---|---|---|---|---|---|
| | Saint-Étienne | Free Transfer | |||||
| Bastia | Undisclosed | ||||||
 | Unattached | Released | Later joined  Antalyaspor | ||||
| | Dijon | Free Transfer | |||||
| | AC Ajaccio | Free Transfer | |||||
 | Rosenborg | Undisclosed | |||||
| | Bastia | Undisclosed | |||||
| | Watford | £8M | [4] |
| Date | Player | Loaned to | Return date | Notes | |||
|---|---|---|---|---|---|---|---|
 | 1. FC Köln | 30 June 2016 | |||||
 | Nantes | 30 June 2016 | |||||
 | Standard Liège | 30 June 2016 | |||||
 | Charleroi | 30 June 2016 | [5] | ||||
| | Clermont | 30 June 2016 | |||||
 | Sunderland | 30 June 2016 | [6] | ||||
 | Perugia | 30 June 2016 | |||||
| | Auxerre | 30 June 2016 | |||||
 | Gaziantepspor | 30 June 2016 | [7] | ||||
| | Dijon | 30 June 2016 |
See main article: 2015–16 Ligue 1.
See main article: 2015–16 Coupe de la Ligue.
See main article: 2015–16 Coupe de France.