The Serie B di pallanuoto maschile is the third division of the Italian water polo male national championship.

At the end of the regular season the top two teams of each group participate in the play-off phase, from which four winners emerge that achieve promotion to Serie A2.

The teams ranked in tenth place of each group are directly relegated and are joined by the teams defeated in the play-outs.

The play-outs consist of the eighth and ninth placed teams.

This results in a total of eight relegations to Serie C. This article about a water polo competition in Italy is a stub.