The 2005–06 Serie B is the 74th season since its establishment in 1929.

It is the second highest football league in Italy.

Cremonese, Rimini, Mantova and Avellino had been promoted from Serie C, while Bologna, Brescia and Atalanta had been relegated from Serie A.

These are the 22 teams which took part in the Serie B 2005-06: hc = higher classified team in the regular season