| 2003 NIFL season | |
|---|---|
| League | National Indoor Football League |
| Sport | indoor American football |
| Regular season | |
| Season champions | Ohio Valley Greyhounds |
| Playoffs | |
| Atlantic champions | Ohio Valley Greyhounds |
| Atlantic runners-up | Lake Charles Land Sharks |
| Pacific champions | Utah Warriors |
| Pacific runners-up | Omaha Beef |
| Indoor Bowl III | |
| Champions | Ohio Valley Greyhounds |
| Runners-up | Utah Warriors |
The 2003 National Indoor Football League season was the third season of the National Indoor Football League (NIFL). The league champions were the Ohio Valley Greyhounds, who wrapped up a perfect season by defeating the Utah Warriors in Indoor Bowl III and becoming the first team in league history to win back-to-back titles.