The 31-year-old has made over 200 appearances for the club since making his professional bow back in 2005.
Robshaw helped them to lift the Premiership title back in 2012 and is an integral part of the squad despite relinquishing the captaincy to scrum-half Danny Care.
"I am extremely proud to have re-signed with the club who gave me my first chance as a player and I've cheered for since I was a child," he said.
"The coaching team have recruited well and we have our sights firmly set on getting silverware this year."
Robshaw also captained England in 42 Test matches, winning 25 of them before handing over the armband to Dylan Hartley in January of last year.