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 chassis (Lola B02/50) and Zytek engines. This season also saw a Light Class running older Lola chassis (Lola B99/50) and Zytek engines. In the Light Class 11 different drivers competed, but only one of them for the whole season.