Mitchell scored an unbeaten 139 from 212 balls with 21 fours and two sixes. as the visitors successfully chased down their victory target of 226, to win by eight wickets on the final day of domestic cricket at Trent Bridge this season.
The 33-year old opener had reached his sixth hundred of the season from 191 deliveries, having hit 16 boundaries.
Joe Clarke, who had been dismissed for a first ball duck on the second day, provided solid support in an unbroken partnership of 106, by making 28 not out.
Resuming on 123 for two, Worcestershire still required a further 103 runs at the start of the day but neither batsman was unduly troubled as they advanced to their target in around 80 minutes of play.
On reaching 83, Mitchell 83 became only the second player to reach 1,000 first class and championship runs for the season, following Kumar Sangakkara to that landmark.
He celebrated his century enthusiastically, by lofting Samit Patel for a couple of sixes over extra cover and he hit the same bowler for the winning runs to bring up Worcestershire’s first championship win at Trent Bridge since 2000. The success also completed an outstanding treble for the New Road side, who have beaten Notts this season in all three formats of the game.
The outcome also ensured that Chris Read was denied the fairy-take ending to his Trent Bridge career. Having received a standing ovation and a guard of honour as he made his way out to bat on the third day, the 39-year old, who retires at the end of the season, was warmly applauded from the field by players and officials from both sides.
Worcestershire claim 20 points for the victory, closing the gap on Division Two leaders Nottinghamshire to just 15 points; with both counties having just two matches remaining.