The current season of The Ultimate Fighter is
Season 14 : Team Bisping vs. Team Miller. They already recorded it and it's about to air later this month. They held tryouts for season 14 back in March.
As for Season 15, the UFC just signed a
huge television deal in the US with the Fox Sports network. As a result, they are going to change the format of the Ultimate Fighter to some sort of
Live format for the TUF fights. Details haven't been divulged yet.