The 30-year-old England international, who signed from Leicestershire in 2012, enjoyed a prolific season with the ball in 2016 taking 81 wickets in all competitions.
He topped the Outlaws’ wicket-taking charts in each of the white ball formats, as well as contributing 45 dismissals at 29.46 in the first-class game.
Gurney, who was capped in 2014 and has 12 full international appearances to his name, has amassed 306 wickets across his five seasons at Trent Bridge.
“Harry has taken massive strides during his time with us and he’s developed into one of the most senior players at the club,” said Nottinghamshire director of cricket Mick Newell.
“He bowls in pressure situations, particularly with the white ball, and does it very well - and in four-day cricket he has the knack of getting wickets in clusters.
“At a time when we have a number of promising young seamers around the club, he sets a great example and will now continue to do that for at least the next three years.”
Gurney’s existing contract was due to expire at the conclusion of the 2017 season.
He joins fellow England international Alex Hales, Academy graduates Tom Moores and Ben Kitt and batsman Greg Smith in recently committing his future to Nottinghamshire.