The 28-year-old is currently sidelined with a knee injury, but Eddie Howe has opted to show his faith in the former West Ham man but tying him down to new terms.
Stanislas joined Bournemouth from Burnley on a free transfer back in 2014 and has gone on to make 87 appearances for the club to date, scoring 19 goals.
Speaking to the club's official website, Stanislas could barely hide his delight, saying: "It's a nice feeling to get rewarded for some good work over the last couple of years.
"As soon as it was there I wanted to get it signed and then get my head down and start focusing on improving over the next few years as well.
"I spoke to the gaffer and he was keen to get something done and signed. That shows the faith the manager has put in me - that is something that I really appreciate."
Bournemouth chief executive Neill Blake was similarly pleased, adding: "I'm delighted that Junior has extended his stay with us.
"He has been an important part of the club for a number of years both on and off the pitch, a key performer in the Premier League and someone who is a real threat for us in the final third.
"Junior is an experienced player but we believe his best years are still ahead of him and that is why we were so keen to ensure he remained at AFC Bournemouth."
September 7, 2018