The 2005 Trofeo Nazionale C.S.A.I. Formula 3000 Italia was contested over 8 rounds. 9 different teams and 26 different drivers competed. In this one-make formula all drivers had to utilize Lola B02/50-Zytek chassis/engine combination. This season also saw a Light Class running older Lola B99/50-Zytek chassis/engine combination.. In the Light Class, 11 different drivers competed, but only one of them for the whole season.

The scoring system was 10-8-6-5-4-3-2-1 points awarded to the first eight finishers. Additional points were given to the driver who achieved pole position (1 extra point) and to the driver who led the greatest numer of laps in the race (1 extra point).

All races were held in Italy, excluding round at Brno in Czech Republic.

For every race points were awarded: 10 points to the winner, 8 for runner-up, 6 for third place, 5 for fourth place, winding down to 1 point for 8th place. Additional points were awarded to the pole winner (1 point) and to the driver leading the most laps (1 point). Light Class drivers were also able to score points in the main class.

Points system see above.