The news comes on the day that the 24-year-old went past fifty County Championship wickets in a season for the first time in his career.
Robinson took 5 for 24 as Sussex dismissed Leicestershire for 133 in their first innings on day two of the current fixture at The 1st Central County Ground.
A day earlier, the all-rounder reached his one thousandth first-class run during Sussex’s first innings of the match.
Reacting to his new deal, Robinson said: “I’m really pleased to be committing my future to Sussex. I feel it’s the right place for me to continue to develop as a player.
“I’m very ambitious to win trophies and I feel that the club is heading in the right direction and will be challenging for trophies consistently.”
Sussex head coach, Jason Gillespie added: “It’s good timing to be announcing the good news about Ollie; going past fifty Championship wickets for the season is something that highlights just what an important player he’s been for us this year.
“He’s been particularly impressive in red-ball cricket, but has had an impact in all three formats. That’s a tough ask for a fast-bowler, and the fact he’s been able to bowl long spells and stay on the pitch is testament to Robbo’s commitment to looking after his body.
“His batting is an added bonus and something he continues to work hard on.
“I’m stoked that Ollie has agreed to stay with us. He’s a massive part of the future of this squad and it’s an exciting time for him as an individual and us as a club.”
Robinson’s 51 wickets in this year’s Specsavers County Championship put him in joint third-position on the wicket taking list and make him the joint second leading-wicket taker amongst England qualified players.
Since joining the club ahead of the 2015 season, Robinson has taken 169 wickets in 65 appearances across all formats.