Charles, 28, who stars in the film as Daniel Bae, wore a black suit with a slightly unbuttoned white shirt and shiny, black dress shoes.
The actor's girlfriend and Riverdale co-star, Camila, 24, looked stunning a tie-die yellow gown while she had her hair styled in an elegant bun.
Shortly before they attended the premiere, the actress posted an adorable love letter for Charles on Instagram, congratulating him on his new film.
Yara Shahidi, who plays Natasha Kingsley in The Sun Is Also a Star, wore a one-shoulder, blue sequin dress with a pair of light-blue denim jeans and bright red heels.
Fellow Riverdale star Marisol Nichols wore a black, strapless jumper and a white blazer. She completed her outfit with a pair of black stilettos and accessorized with a gorgeous diamond necklace.
Another Riverdale cast member, Drew Ray Tanner, supported good friend Charles on the carpet. The 27-year-old actor wore a grey suit with plaid dress pants and a brown leather shoes.
Francia, 30, looked amazing in a white blazer style dress with silver strappy heels. She left her short brown hair down and accessorized with silver jewelry.
This Is Us star Lyric Ross attended the premiere in a metallic gold tank top and a black leather skirt. She completed her look with a metallic, leopard print blazer and black heels.
The Sun Is Also a Star premieres in U.S theaters on Friday, May 17.
Whose outfit from the premiere do you like best? Let us know in the comments below!