The 26-year-old made 24 appearances and scored five times last season to help the Cherries retain top-flight status.
Stanislas, a former West Ham United player, is currently sidelined with a groin injury.
"It's great to be able to secure his long-term future at the club," chief executive Neill Blake said.
Bournemouth winger Junior Stanislas has signed a new three-year contract which will keep him at the Premier League club until the summer of 2019.