Law enforcement sources tell us Herbo was busted around 5:45 PM near North Wabash Avenue and East Ontario Street, where cops say they found a gun. Herbo's Chi town fans will recognize those streets as he frequently mentions them in his songs.

According to cops, Herbo was arrested and booked for misdemeanor unlawful use of a weapon in a public place.

We're told Herbo has since bonded out and will have to appear in court at a later date, which could cause another setback in his rap career.

Herbo's latest arrest could potentially impact him deeply ... the drill rapper is still dealing with fraud charges he caught following a December 2020 arrest.