The Ireland lock and Six Nations winner has made 157 appearances for the province since his debut against Border Reivers in January 2006.
Toner has enjoyed plenty of success since then, winning three Heineken Cups, an Amlin Cup and three Pro12 titles.
The 28-year-old told Leinster's official website: "It is great to have signed on for another two years with Leinster.
"I have been with the province for almost a decade and during that time the club have invested a lot in my development and have given me the platform to reach my potential and achieve success at both provincial and national level."
Leinster CEO Mick Dawson added: "We are delighted that Devin has signed an IRFU contract which keeps him at Leinster up to the end of the 2017 season.
"Devin's skill, athleticism and leadership add greatly to our environment and he continues to grow and develop as a player who has a huge role to play at Leinster over the next few seasons."