Jabeur, the world number five from Tunisia, avenged her defeat to Bencic in last year's final with a hard-fought 7-6, 6-4 victory in just over two hours.
Switzerland's Bencic was forced to make a quick turnaround on Sunday, completing a 7-5, 7-6 weather-disrupted semi-final win over Jessica Pegula (29) before returning to face Jabeur in the final around 30 minutes later.
There was no immediate sign of weariness from the Swiss player as she started strongly to take a 5-3 lead in the opening set.
However, Jabeur held and then conjured a break to level at 5-5 before holding again for a 6-5 lead.
Bencic was soon in trouble on her serve, but fought back brilliantly from 0-40 down to hold and force a tie-break.
Again momentum swung back and forth, with Bencic holding two set points after opening up a 6-4 lead in the tie-break before Jabeur reeled off four straight points to take the set.
Jabeur then raced into a 4-1 lead in the second set, and although Bencic responded well, Jabeur was soon serving for the match at 5-4 up.
Bencic squandered three break points that would have levelled the set at 5-5 before Jabeur eventually converted her second match point to seal the fourth title of her career.
