The 2005–06 LEB 2 season was the 6th season of the LEB Plata, second league of the Liga Española de Baloncesto and third division in Spain.

It is also named Adecco Plata for sponsorship reasons.

This is a round robin, where each team will play twice against every rival.

After the regular season, the eight first qualified teams played a playoff, were the two finalists promoted to LEB.

If two or more teams have got the same number of winning games, the criteria of tie-breaking are these: