Ireland internationals Devin Toner, Shane Jennings and Sean O'Brien have agreed new deals to remain with Leinster.
The trio are joined by emerging duo Fergus McFadden and Jack McGrath in committing to the club.
Jennings and O'Brien have signed three-year deals, while Toner, McFadden and McGrath have committed to the Dublin side for the next two seasons.
And Jennings, who has made 118 appearances for the province, believes the future is bright at Leinster.
The 29-year-old said: "It's an exciting time for the province and I am delighted to re-sign with Leinster for a further three years.
"There's a determination within the group to push on and continue to improve and the aspirations of my team-mates as well as the coaching staff was a key factor in my decision to stay.
"It has always been my ambition to be a part of a successful Leinster side and I have no doubt that with the competitive nature of the up-and-coming and established members of our squad that the future looks bright."
O'Brien, a graduate of the Leinster academy, is confident the club can enjoy domestic and European success over the next few years.
"I am delighted to commit myself for a further three years to Leinster," he said.
"I believe there is something very special about this club and with so many talented players at our disposal - and with the management team working well - I am confident that the great achievements of recent years can be matched or even maybe surpassed," he said.
"While it was flattering to have interest from overseas, I desperately want to be part of the Leinster story for the foreseeable future."
Toner, who has been capped three times, believes the competition for places has motivated the players.
He said: "I think that the high competition levels within the squad this year have driven us all on and the upshot of that has been our recent good run of form.
"I have been very fortunate to have worked alongside the likes of Mal, Trev, Leo and Hinesy in recent years and there's a really strong base within the squad where we're all trying to help each other and improve one another. I'm really pleased to sign up with Leinster."