The 77-year-old comedienne showed off her cleavage in a low-cut animal-print dress and even donned a Snooki-style bouffant wig.
Poking her right breast, Rivers’ Fashion Police co-star Kelly Osbourne quipped: “Look how hard your nipples are.”
And even Snooki appeared impressed.
“These look better than mine,” the 22-year-old reality star said, cupping Rivers’ boobs.
Rivers sported her Snooki costume for a special Halloween edition of E! television network’s Fashion Police, which aired yesterday in the US.
But the US funnywoman was left open-mouthed when the real Jersey Shore star stepped out into the studio.
“You stole my frickin’ look,” Snooki laughed as she struck a pose with Rivers.
“Two simple girls with a dream. Who looks better?” Rivers joked.