The Olympics red carpet in Paris is glittering, and it ain't the shine off the metals 'cause those haven't been won yet ... it's all the superstars twinkling at a pre-Olympics event.

Some of the biggest athletes and entertainers in the world -- from LeBron James to Serena Williams to Snoop Dogg and everyone in between -- pulled up to the Prelude to the Olympics ... a star-studded party open cohosted by some of the world's most powerful people before Olympic Opening Ceremonies kick off tomorrow.

Two blonde Hollywood bombshells -- Charlize Theron and Elizabeth Banks -- hit the red carpet in a couple fabulous dresses ... CT looked angelic in all white while EB pulled off a black cocktail dress with a blue accessory draping down from her hip.

While Banks and Theron can party into the wee hours of the morning, tennis star Naomi Osaka may want to leave the prelude a little earlier ... 'cause she's got her first women's singles match Saturday against Germany's Angelique Kerber.

Jeremy Allen White and Alan Cumming each walked the carpet in fashionable tuxes tuned to their personalities ... with the brooding 'Bear' fitted in a black suit while two-time Tony winner Cumming rocked a svelte orange number.

BTW JAW's lady love Rosalía walked the carpet too -- though there don't appear to be any pics of them together. Ya never know with those two ... they could always dip out halfway through the party for a cigarette and une promenade romantique.

Among the other bold-faced names ... Steven Spielberg, NBA legend Tony Parker, Ashlyn Harris, Sophia Bush, Aly Raisman, Jeffrey Katzenberg and many more.

So, a night of hobnobbing among the famous fans and athletes ... but, expect all-out war for medals over the next month!