The expanded team will include three new female gladiators called Siren, Amazon and Cyclone and three male athletes -- Warrior, Doom and Goliath.
Sky1 describes Warrior as a "savage beast who takes no prisoners" while Siren is "the goddess of perilous seduction, expect no mercy".
Ice and Destroyer will leave the show along with presenter Kirsty Gallacher who is being replaced by Caroline Flack. Flack will join Ian Wright for the new series which starts in January.
Original ITV gladiator Wolf, who took part in a "Legends" special earlier this year, will return as the gladiators' manager.
However, the original referee John Anderson, famous for his catchphrase "Gladiators ready", is stepping down to be replaced by boxing referee John Coyle.
Coyle will be joined by Hugh Watkins, a rugby union referee, who will take on the new role of 'Gladiators' video referee and will assist with any controversial decisions.
Sky1 is expanding the team to cope with a new production schedule which means that two shows will be filmed a day.
Steve Jones, commissioning editor for Sky1, 2 and 3, said: "Our new Gladiators are an awesome sight to behold. Bigger, stronger, and even more unstoppable than before.
"We have found some brilliant characters and they will all be at the top of their game for fear of getting a rollicking from their new manager."
Wolf said: "I was blown away by the buzz I felt competing in the Gladiators arena again. It was like I'd never been away.
"The audience was phenomenal and clearly wanted more of the Wolfman. And now I'm back as manager, and I'm in charge!"