Jack Harlow always has time for his fans ... even the youngest ones on the outskirts.
The rapper cleared a path this weekend for a 10-year-old who was seeking a photo with him at the Kentucky Derby, but was blocked off by a gaggle of security guards flanking him on all sides.
The kid's mother, Katy Mackin, tells TMZ ... her daughter, Veronica, saw Jack down on the race track where he was scheduled to do the "riders up" call -- signaling the jockeys to take their starting positions on the horses.