The man accusing "Melrose Place" star Jamie Luner of performing oral sex on him when he was only 16 ... claims she plied him with drugs and taped their encounter, but she's calling BS.
Anthony Oliver tells TMZ ... he met Luner through his older brother in the late 90s. He was not an actor, but scored an invitation to a party at Luner's Studio City home in 1998. Anthony claims she loosened him up with the booze and the drugs before they went into a room with a third person.
Anthony claims the other person was recording video while Luner performed oral sex.
We broke the story ... Anthony filed a police report last month with LAPD. As for why he waited 20 years -- he says the therapist he's seeing for alcoholism suggested he report the alleged incident.
He also says he told his family back in 1998, but because his mother was a local politician at the time ... they were hesitant to go public.
Jamie's rep tells us she "emphatically denies these allegations."