Lil Wayne claims he did NOT pass out drunk before a Bahama concert in 2009 ... resulting in a canceled show -- this according to new legal docs obtained by TMZ.
TMZ broke the story ... Weezy was sued back in 2009 by a promotion company called Red City Entertainment -- which claimed it fronted $432,000 for a concert in the Bahamas, but Weezy drunkenly slept through the whole thing.
When he failed to show, Red Light claims cops showed up to the rapper's hotel room and found him unconscious.
But Weezy insists it's all BS -- claiming, "At no point [that night] did I become so intoxicated that I passed out on a bed in my suit, or anywhere else."
Wayne says the real reason he didn't show up was because the concert was canceled -- he can't remember exactly why ... but believes it had something to do with technical difficulties, like lighting and sound problems.
Wayne is now asking the court for a judgment in his favor.