Several drivers failed to set times at a soaking wet Autodromo Enzo e Dino Ferrari on Friday, but Victor Martins set the quickest after just five tours of the Imola circuit.
Most of the field headed out early, with times eventually spread over five seconds apart.
Ido Cohen and Kaylen Frederick exchanged top spot before BWT Alpine F1 Team junior Martins set a time which would not be beaten.
The session was punctuated by red flags for off-track excursions into the gravel traps and walls lining the circuit.
The local Ferrari Driver Academy prospects of Arthur Leclerc and Oliver Bearman (both Prema Racing) found themselves in the lower reaches of the timesheet, with Leclerc finishing over 11 seconds off Martins’ pace.
Each red flag led to another with incidents for Cohen, David Schumacher, Caio Collet, Kush Maini and Hunter Yeany.
Martins ended the curtailed session on top, ahead of Isack Hadjar, Roman Stanek and Frederick.
The Van Amersfoort Racing pair of Rafael Villagomez and Franco Colapinto led home Zane Maloney, Cohen and the returning Oliver Rasmussen.
FIA Formula 3 Championship Practice Result – Imola
| Pos. | No. | Name | Nat. | Team | Time/Gap |
| 1 | 7 | Victor Martins | FRA | ART Grand Prix | 1:50.134 |
| 2 | 18 | Isack Hadjar | FRA | Hitech Grand Prix | +0.034s |
| 3 | 2 | Roman Stanek | CZE | Trident | +0.825s |
| 4 | 17 | Kaylen Frederick | USA | Hitech Grand Prix | +1.149s |
| 5 | 30 | Rafael Villagomez | MEX | Van Amersfoort Racing | +1.190s |
| 6 | 29 | Franco Colapinto | ARG | Van Amersfoort Racing | +1.240s |
| 7 | 3 | Zane Maloney | BAR | Trident | +1.448s |
| 8 | 26 | Zak O’Sullivan | GBR | Carlin | +1.638s |
| 9 | 23 | Ido Cohen | ISR | Jenzer Motorsport | +1.640s |
| 10 | 1 | Oliver Rasmussen | DEN | Trident | +1.783s |
| 11 | 19 | Nazim Azman | MAL | Hitech Grand Prix | +2.043s |
| 12 | 20 | David Vidales | SPA | Campos Racing | +2.407s |
| 13 | 31 | Reece Ushijima | JPN | Van Amersfoort Racing | +2.471s |
| 14 | 21 | Hunter Yeany | USA | Campos Racing | +2.632s |
| 15 | 25 | William Alatalo | FIN | Jenzer Motorsport | +2.961s |
| 16 | 22 | Josep Maria Marti | SPA | Campos Racing | +3.074s |
| 17 | 8 | Gregoire Saucy | SUI | ART Grand Prix | +3.079s |
| 18 | 28 | Enzo Trulli | ITA | Carlin | +4.402s |
| 19 | 24 | Federico Malvestiti | ITA | Jenzer Motorsport | +4.423s |
| 20 | 10 | Caio Collet | BRA | MP Motorsport | +5.254s |
| 21 | 11 | Alexander Smolyar | FIA | MP Motorsport | +5.849s |
| 22 | 27 | Brad Benavides | USA | Carlin | +6.191s |
| 23 | 4 | Arthur Leclerc | MON | Prema Racing | +11.239s |
| 24 | 12 | Kush Maini | IND | MP Motorsport | +16.207s |
| 25 | 14 | Laszlo Toth | HUN | Charouz Racing System | No time set |
| 26 | 16 | Francesco Pizzi | ITA | Charouz Racing System | No time set |
| 27 | 5 | Jak Crawford | USA | Prema Racing | No time set |
| 28 | 6 | Oliver Bearman | GBR | Prema Racing | No time set |
| 29 | 15 | David Schumacher | GER | Charouz Racing System | No time set |
