Lil Wayne: Suspect in Nightclub Assault

Lil Wayne slugged a nightclub doorman after the BET Awards ... according to the doorman, who's filed a battery report with LAPD.

The bouncer was working the door Sunday night at Hyde nightclub on Sunset ... where Wayne and 2 Chainz were hosting an after-party. Law enforcement sources tell us things got heated when several members of Weezy's entourage got turned away at the door.

We're told Wayne and the bouncer started arguing about who was getting in, and the bouncer says that's when Wayne uncorked a punch to his face.

The Hyde staffer went to a hospital for treatment, and called police ... who are investigating and want to talk to Wayne. Our sources in Wayne's camp say he denies punching the bouncer, and says the guy actually worked in Wayne's VIP section all night.

They say there was a brief altercation, but only because the bouncer mistakenly grabbed Wayne by the arm ... not realizing who he was. He later apologized, according to our Wayne sources.