The Atlanta rapper was performing his first New Zealand show and was nearing the end of his set when the incident happened.
Footage supplied to the Herald shows the fan balancing on the Powerstation's second level balcony railing before diving into the crowd below.
Those below him, however, failed to catch the fan and he crashed heavily into the floorboards.
The incident was described as "sickening" and led to gasps echoing around the venue.
The rapper and his entourage also fled the stage after the incident, but later returned to finish the set.
The footage shows the fan quickly recovering and jumping around to the next song.
Campbell says the jumper was quickly escorted out of the venue, and medics attended to a punter who he "clipped" on the way down.
But he advised him not to return to the venue for a while.
"If he had purchased a ticket for another show and he came through in the next month or so, I'd be inclined to give him his money back and tell him to go home and think about it," he says.
"It'd be better if he wasn't in the Powerstation for a little while."
• Do you known who it is? Email us here.
• Read the Herald's full review of the show here.