| Competition: | Regionalliga |
| Season: | 2002–03 |
| Promoted: | Erzgebirge Aue VfL Osnabrück SpVgg Unterhaching Jahn Regensburg |
| Relegated: | SC Verl SV Babelsberg 03 Bayer Leverkusen (A) Dresdner SC SV Darmstadt 98 Eintracht Frankfurt (A) Borussia Neunkirchen |
| Matches: | 648 |
| Total Goals: | 1821 |
| League Topscorer: | Francisco Copado (SpVgg Unterhaching) - 24 |
| Attendance: | 1,740,933 |
| Average Attendance: | 2,686 |
| Prevseason: | 2001–02 |
| Nextseason: | 2003–04 |
The 2002–03 Regionalliga season was the ninth season of the Regionalliga at tier three (III) of the German football league system.
The Regionalliga was split into two divisions, the Regionalliga Nord and the Regionalliga Süd. The league champions, Erzgebirge Aue and SpVgg Unterhaching, and the runners-up in both divisions, VfL Osnabrück and Jahn Regensburg, were promoted to the 2003–04 2. Bundesliga.
SV Babelsberg 03, 1. FC Saarbrücken, 1. FC Schweinfurt 05 and SpVgg Unterhaching came down from the 2001–02 2. Bundesliga, replacing VfB Lübeck, Eintracht Braunschweig, Wacker Burghausen and Eintracht Trier.
Borussia Dortmund (A), Dynamo Dresden, Hamburger SV (A), 1. FC Köln (A), FC Augsburg, Eintracht Frankfurt (A) Borussia Neunkirchen and SC Pfullendorf were promoted from the Oberliga, replacing 1. FC Magdeburg, Fortuna Düsseldorf, Fortuna Köln, VfR Mannheim, VfB Stuttgart (A), SpVgg Ansbach and Borussia Fulda.
Five teams were due to be relegated, but Stuttgarter Kickers and Sportfreunde Siegen were reprieved because two of the relegated teams from the 2. Bundesliga, SSV Reutlingen and SV Waldhof Mannheim, could not achieve a Regionalliga license, and dropped another level, to the Oberliga.
| Player | Club | Goals | |
|---|---|---|---|
| 1. |  Francisco Copado | SpVgg Unterhaching | 24 |
| 2. | Mark Römer | SC Pfullendorf | 22 |
| 3. | Veselin Popović | 1. FC Schweinfurt 05 | 20 |
| 4. | Thomas Ollhoff | TSG Hoffenheim | 19 |
| 5. | Jörg Reeb | FC Augsburg | 15 |
| 6. | Christoph Teinert | TSG Hoffenheim | 14 |
| 7. |  Miguel Coulibaly | FC Augsburg | 13 |
 Sead Mehić | SV Wehen | ||
| Vlado Papić | Jahn Regensburg | ||
 András Tölcséres | Jahn Regensburg |
