Kandi, 42, got back from her vacation in Thailand with husband Todd Tucker just in time to see Riley, 16, before she headed off for her big night.
"My baby is going to the prom!" Kandi exclaimed on one of her Instagram stories.
Riley looked stunning in a red dress with heels that had an R on each strap.
Kandi's RHOA costars Eva Marcille and Cynthia Bailey both complimented Riley on her fierce prom look.
Her stepfather Todd also showed some love for Riley on her special night. "@riley you killed it! You look amazing! Classy, and beautiful! Have fun, not too much I got people watching you! Lol!"
What are your thoughts on Riley's prom ensemble? Sound off in the comments!