| 26 Nov 09 | D. Campbell DJ Campbell |  Leicester CityLEI | → |  Derby CountyDER | Loan |
| 22 Oct 09 | B. Hughes Bryan Hughes |  Hull CityHUL | → | Derby CountyDER | Loan |
| 22 Oct 09 | B. Hughes Bryan Hughes | Hull CityHUL | → | Derby CountyDER | Loan |
| 16 Oct 09 | A. Mendy Arnaud Mendy | Derby CountyDER | → |  Grimsby TownGRI | Loan |
| 03 Oct 09 | M. Dudley Mark Dudley | Derby CountyDER | → | ATXAlfreton TownAlfreton Town | Loan |
| 25 Sept 09 | F. Stoor Fredrik Stoor |  FulhamFUL | → | Derby CountyDER | Loan |
| 25 Sept 09 | F. Stoor Fredrik Stoor | FulhamFUL | → | Derby CountyDER | Loan |
| 18 Sept 09 | J. Vaughan James Vaughan |  EvertonEVE | → | Derby CountyDER | Loan |
| 18 Sept 09 | J. Vaughan James Vaughan | EvertonEVE | → | Derby CountyDER | Loan |
| 01 Sept 09 | J. Stewart Jordan Stewart | Derby CountyDER | → |  Sheffield UnitedSHU | Free |
| 01 Sept 09 | L. Hendrie Lee Hendrie | Sheffield UnitedSHU | → | Derby CountyDER | Free |
| 28 Aug 09 | P. Dickov Paul Dickov | Leicester CityLEI | → | Derby CountyDER | Loan |
| 21 Aug 09 | L. Varney Luke Varney | Derby CountyDER | → |  Sheffield WednesdaySHW | Loan |
| 20 Aug 09 | Medi Abalimba |  Southend UnitedSOUT | → | Derby CountyDER | Undisclosed |
| 07 Aug 09 | J. Livermore Jake Livermore |  Tottenham HotspurTOT | → | Derby CountyDER | Loan |
| 07 Aug 09 | J. Livermore Jake Livermore | Tottenham HotspurTOT | → | Derby CountyDER | Loan |
| 01 Aug 09 | S. Deeney Saul Deeney |  Burton AlbionBRT | → | Derby CountyDER | Free |
| 15 Jul 09 | S. Barker Shaun Barker |  BlackpoolBLP | → | Derby CountyDER | Undisclosed |
| 15 Jul 09 | L. Nyatanga Lewin Nyatanga | Derby CountyDER | → |  Bristol CityBRC | Undisclosed |
| 14 Jul 09 | L. Dick Liam Dick | Derby CountyDER | → |  Brighton & Hove AlbionBHA | Undisclosed |
| 08 Jul 09 | L. Price Lewis Price | Derby CountyDER | → |  BrentfordBRE | Loan |
| 01 Jul 09 | J. Buxton Jake Buxton | Burton AlbionBRT | → | Derby CountyDER | Free |
| 01 Jul 09 | Ben Pringle | ITXIlkeston TownIlkeston Town | → | Derby CountyDER | Free |
| 30 Jun 09 | T. Mears Tyrone Mears | Derby CountyDER | → |  BurnleyBUR | 500000 |
| 30 Jun 09 | T. Mears Tyrone Mears | Derby CountyDER | → | BurnleyBUR | 500000 |
| 29 Jun 09 | D. Moxey Dean Moxey |  Exeter CityEXE | → | Derby CountyDER | Undisclosed |
| 25 Jun 09 | L. Croft Lee Croft |  Norwich CityNOR | → | Derby CountyDER | Free |
| 11 Jun 09 | M. Sterjovski Mile Sterjovski | Derby CountyDER | → |  Perth GloryPER | Free |
| 11 Jun 09 | M. Sterjovski Mile Sterjovski | Derby CountyDER | → | Perth GloryPER | Free |
| 20 Mar 09 | L. Varney Luke Varney | Derby CountyDER | → | Sheffield WednesdaySHW | Loan |
| 16 Mar 09 | A. Prijovic Aleksander Prijovic | Derby CountyDER | → |  Northampton TownNHT | Loan |
| 13 Mar 09 | B. Bannan Barry Bannan |  Aston VillaAVL | → | Derby CountyDER | Loan |
| 13 Mar 09 | L. Dick Liam Dick | Derby CountyDER | → |  Leeds UnitedLEE | Loan |
| 13 Mar 09 | B. Bannan Barry Bannan | Aston VillaAVL | → | Derby CountyDER | Loan |
| 10 Mar 09 | P. Simmons Paris Simmons | Derby CountyDER | → |  Lincoln CityLCN | Loan |
| 09 Mar 09 | J. Eustace John Eustace |  WatfordWAT | → | Derby CountyDER | Loan |
| 02 Feb 09 | L. Price Lewis Price | Derby CountyDER | → |  Luton TownLUT | Loan |
| 02 Feb 09 | C. Davis Claude Davis | Derby CountyDER | → |  Crystal PalaceCRY | Loan |
| 31 Jan 09 | G. Barnes Giles Barnes | Derby CountyDER | → | FulhamFUL | Loan |
| 31 Jan 09 | C. Porter Chris Porter |  MotherwellMOT | → | Derby CountyDER | Undisclosed |
| 31 Jan 09 | G. Barnes Giles Barnes | Derby CountyDER | → | FulhamFUL | Loan |
| 31 Jan 09 | C. Porter Chris Porter | MotherwellMOT | → | Derby CountyDER | Undisclosed |
| 27 Jan 09 | A. Prijovic Aleksander Prijovic | Derby CountyDER | → |  Yeovil TownYEO | Loan |
| 05 Jan 09 | S. Hines Seb Hines |  MiddlesbroughMID | → | Derby CountyDER | Loan |
| 05 Jan 09 | S. Hines Seb Hines | MiddlesbroughMID | → | Derby CountyDER | Loan |