The 2004 Formula Nippon Championship was contested over 9 rounds, with 8 teams and 17 drivers competed in the series. All teams had to use Lola chassis (Lola B3/51) and Mugen Honda (Mugen MF308) engines.
| Team | # | Driver | Chassis | Engine | Rounds |
|---|---|---|---|---|---|
| ADiRECT Team 5ZIGEN | 1 | | Lola B3/51 | Mugen MF308 | All |
| 2 | | All | |||
| Yellow Hat Kondo Racing Team | 3 | | Lola B3/51 | Mugen MF308 | All |
| 4 | | All | |||
| Team LeMans | 7 | | Lola B3/51 | Mugen MF308 | All |
| 8 | | All | |||
| Cosmo Oil Racing Team Cerumo | 11 | | Lola B3/51 | Mugen MF308 | All |
| 12 | | 6–9 | |||
| mobilecast Team Impul | 19 | | Lola B3/51 | Mugen MF308 | All |
| 20 | | All | |||
| LeMans Spirit | 25 | | Lola B3/51 | Mugen MF308 | All |
| Carrozzeria Team MOHN | 27 | | Lola B3/51 | Mugen MF308 | 4–5, 8 |
| 28 | | All | |||
| PIAA Nakajima Racing | 31 | | Lola B3/51 | Mugen MF308 | All |
| 32 | | All | |||
| DoCoMo Team Dandelion Racing | 40 | | Lola B3/51 | Mugen MF308 | All |
| 41 | | All |
| Race | Track | Date | Pole position | Fastest race lap | Winning driver | Winning team |
|---|---|---|---|---|---|---|
| 1 | | 28 March | | | | PIAA Nakajima Racing |
| 2 | | 2 May | | | | DoCoMo Team Dandelion Racing |
| 3 | | 6 June | | | | PIAA Nakajima Racing |
| 4 | | 4 July | | | | DoCoMo Team Dandelion Racing |
| 5 | | 1 August | | | | ADiRECT Team 5ZIGEN |
| 6 | | 29 August | | | | mobilecast Team Impul |
| 7 | | 19 September | | | | PIAA Nakajima Racing |
| 8 | | 24 October | | | | mobilecast Team Impul |
| 9 | | 7 November | | | | mobilecast Team Impul |
| Position | 1st | 2nd | 3rd | 4th | 5th | 6th |
|---|---|---|---|---|---|---|
| Points | 10 | 6 | 4 | 3 | 2 | 1 |
| Rank | Name | SUZ | SGO | MOT | SUZ | SGO | MIN | MYS | MOT | SUZ | Points |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | | 8 | 1 | 8 | 1 | 4 | 8 | 9 | 2 | 3 | 33 |
| 2 | | 2 | 4 | 1 | 8 | Ret | Ret | 1 | 3 | 7 | 33 |
| 3 | | 12 | 2 | 2 | 3 | 7 | 7 | 10 | 1 | 2 | 32 |
| 4 | | Ret | 6 | 4 | 2 | 10 | 1 | 7 | Ret | 1 | 30 |
| 5 | | 13 | 3 | Ret | 5 | 3 | 2 | 3 | Ret | 4 | 23 |
| 6 | | 5 | 12 | 5 | 4 | 1 | 6 | Ret | 5 | 6 | 21 |
| 7 | | 1 | 9 | 9 | 7 | 2 | Ret | 6 | 9 | 8 | 17 |
| 8 | | 10 | 11 | 3 | 13 | Ret | 4 | 5 | 4 | 12 | 12 |
| 9 | | 7 | 7 | Ret | 10 | 6 | 10 | 2 | Ret | 10 | 7 |
| 10 | | 3 | 5 | 6 | Ret | Ret | 11 | 8 | 10 | 13 | 7 |
| 11 | | 4 | NC | 12 | 9 | DSQ | 12 | 4 | 6 | Ret | 7 |
| 12 | | 6 | 13 | 10 | Ret | 12 | 3 | Ret | Ret | 11 | 5 |
| 13 | | 11 | 10 | 7 | 11 | 8 | 5 | Ret | Ret | 5 | 4 |
| 14 | | Ret | NC | Ret | 6 | 5 | 9 | Ret | 7 | 9 | 3 |
| 15 | | 9 | 8 | 11 | Ret | 11 | Ret | Ret | 11 | 14 | 0 |
| 16 | | 12 | 9 | 8 | 0 | ||||||
| 17 | | Ret | 11 | Ret | 15 | 0 |
| Rank | Team | Car | SUZ | SGO | MOT | SUZ | SGO | MIN | MYS | MOT | SUZ | Points |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | mobilecast Impul | 19 | Ret | 6 | 4 | 2 | 10 | 1 | 7 | Ret | 1 | 62 |
| 20 | 12 | 2 | 2 | 3 | 7 | 7 | 10 | 1 | 2 | |||
| 2 | PIAA Nakajima | 31 | 2 | 4 | 1 | 8 | Ret | Ret | 1 | 3 | 7 | 50 |
| 32 | 1 | 9 | 9 | 7 | 2 | Ret | 6 | 9 | 8 | |||
| 3 | DoCoMo Dandelion | 40 | 8 | 1 | 8 | 1 | 4 | 8 | 9 | 2 | 3 | 40 |
| 41 | 7 | 7 | Ret | 10 | 6 | 10 | 2 | Ret | 10 | |||
| 4 | LeMans LeMans Spirit | 7 | 13 | 3 | Ret | 5 | 3 | 2 | 3 | Ret | 4 | 37 |
| 8 | 11 | 10 | 7 | 11 | 8 | 5 | Ret | Ret | 5 | |||
| 25 | 10 | 11 | 3 | 13 | Ret | 4 | 5 | 4 | 12 | |||
| 5 | ADiRECT 5ZIGEN | 1 | 5 | 12 | 5 | 4 | 1 | 6 | Ret | 5 | 6 | 26 |
| 2 | 6 | 13 | 10 | Ret | 12 | 3 | Ret | Ret | 11 | |||
| 6 | Yellow Hat Kondo | 3 | 3 | 5 | 6 | Ret | Ret | 11 | 8 | 10 | 13 | 10 |
| 4 | Ret | NC | Ret | 6 | 5 | 9 | Ret | 7 | 9 | |||
| 7 | Cosmo Oil Cerumo | 11 | 4 | NC | 12 | 9 | DSQ | 12 | 4 | 6 | Ret | 7 |
| 12 | Ret | 11 | Ret | 15 | ||||||||
| 8 | Team MOHN | 27 | 12 | 9 | 8 | 0 | ||||||
| 28 | 9 | 8 | 11 | Ret | 11 | Ret | Ret | 11 | 14 |