Nicki Minaj and Katy Perry -- We're BARBIE DOLLS Now!

Sucks that a guy with no genitals is about to get a shot with Nicki Minaj and Katy Perry ... because TMZ has learned they are both about to become Barbie Dolls!!

Sources close to the plastic factory tell TMZ ... Mattel has already begun production on ONE single Nicki doll and and ONE single Katy doll.

We're told Nicki's doll will include "every signature detail, right down to the tattoo on Nicki's left arm."

The Nicki doll will be auctioned off online on Dec. 7 -- and proceeds will benefit the Project Angel Food organization.