| 2004 Top League Challenge Series | |
|---|---|
| Countries | Japan |
| Date | 10 – 24 January 2004 |
| Champions | Toyota Verblitz (1st title) |
| Runners-up | IBM Big Blue |
| Promoted | IBM Big Blue Toyota Verblitz |
| Matches played | 6 |
The 2004 Top League Challenge Series was the 2004 edition of the Top League Challenge Series, a second-tier rugby union competition in Japan, in which teams from regionalised leagues competed for promotion to the Top League for the 2004–05 season. The competition was contested from 10 to 24 January 2004.
IBM Big Blue and Toyota Verblitz won promotion to the 2004–05 Top League, while Kyuden Voltex and Toyota Industries Shuttles progressed to the promotion play-offs.