Two goals from defender Alex Rosenthal plus one apiece from Dovid Korman and Avidan Last saw them run out worthy winners against the Raiders in Borehamwood on Wednesday night.
Korman opened the scoring midway through the first half with a scorching finish past Dan Cohen.
Last doubled the lead with half time approaching following another fine diagonal pass that dissected the Raiders backline.
Raiders improved in the second half and it needed an excellent save from keeper Russell Corin to maintain Hendon's two-goal lead.
But the Reds finished the game on the front foot, with the rampaging Rosenthal producing two fine finishes - the first beating Cohen at his near post followed by another in the dying seconds to flick home an excellent cross from Ben Lauffer.
Jubilant Hendon boss David Garbacz told JC Sport: "You can't under-estimate how great an achievement winning the treble is.
"The boys have been tremendously focused, showed a great attitude and there have been no weak links in the squad. I'm really proud of them all.
"When we arrived here tonight, we made a really concerted effort that we'd finish the job and clinch the title and, in front of a nice crowd for an evening game, we wanted to do it in style.
"It was a great performance and we were intense from the off, against a Raiders team who played well."
Commenting on the team's impressive defensive record, Garbacz added: "We set a target at the start of the season to concede no more than 15 goals. We have achieved that and there is no doubt that this team is built on a solid defence, with Josh Lipman and Alex Rosenthal outstanding, along with keeper Russell Corin."
Hendon will conclude a memorable season with a double-header against Brady Maccabi A on Sunday.
