Steelers' Le'Veon Bell DISSES CINCINNATI In New Rap Song

The Bengals ain't gonna like this one ...

Steelers running back Le'Veon Bell -- who's also a rapper -- just dropped a NEW TRACK taking aim at Cincinnati ... just 7 weeks before they're set to do battle on the field.

The song is "Rapping Athlete" -- in which Bell spits the lyrics:

"All these haters @ me ...
You need to check my rap sheet ...
You better take the backseat like you play in Cincinnati."

There's a ton of bad blood between the Steelers and the Bengals -- in fact, it was Bengals LB Vontaze Burfict who ended Bell's season last year during a Week 8 matchup.

As far as the rivalry goes, the Steelers have won 6 out of the last 7 matchups ... so, advantage Le'Veon.

By the way, he also name drops Johnny Manziel ... saying he's balling the ex-QB -- but back when he was in college!