| Country: | Monaco |
| Grand Prix: | Monaco |
| Round No: | 3 |
| Season No: | 12 |
| Year: | 2005 |
| Location: | Circuit de Monaco, Monte Carlo, Monaco |
| Course: | Street circuit |
| Course Km: | 3.340 |
| Course Mi: | 2.08 |
| Date R1: | 21 May |
| Laps R1: | 44 |
| Pole Driver Country: | FIN |
| Pole Driver: | Heikki Kovalainen |
| Pole Team: | Arden International |
| Pole Time: | 1:24.665 |
| First Driver Country R1: | GBR |
| First Driver R1: | Adam Carroll |
| First Team R1: | Super Nova International |
| Second Driver Country R1: | ITA |
| Second Driver R1: | Gianmaria Bruni |
| Second Team R1: | Coloni Motorsport |
| Third Driver Country R1: | GER |
| Third Driver R1: | Nico Rosberg |
| Third Team R1: | ART Grand Prix |
| Fast Driver Country R1: | FIN |
| Fast Driver R1: | Heikki Kovalainen |
| Fast Team R1: | Arden International |
| Fast Time R1: | 1:23.864 |
| Fast Lap R1: | 44 |
The 2005 Monaco GP2 round was a GP2 Series motor race held on 21 May 2005 at the Circuit de Monaco in Monte Carlo, Monaco. It was the third race of the 2005 GP2 Series season. The race was used to support the 2005 Monaco Grand Prix.
There was only one race, held on Saturday. Polesitter Heikki Kovalainen finished fifth after an unsuccessful pit-stop, but was able to set the fastest lap. Irishman Adam Carroll, who started third, won the race by a margin of 0.657 seconds from Gianmaria Bruni. Nico Rosberg finished third, to score his first GP2 podium finish.
| Pos | Driver | Points | ||
|---|---|---|---|---|
| 1 |  Heikki Kovalainen | 28 | ||
| 1 | 2 |  Gianmaria Bruni | 26 | |
| 1 | 3 |  Scott Speed | 25 | |
| 1 | 4 |  Adam Carroll | 23 | |
| 1 | 5 |  José María López | 17 |
| Pos | Team | Points | ||
|---|---|---|---|---|
| 1 | Arden International | 32 | ||
| 1 | 2 | Coloni Motorsport | 29 | |
| 1 | 3 | iSport International | 27 | |
| 1 | 4 | Super Nova International | 23 | |
| 1 | 5 | ART Grand Prix | 19 |
