West picked up a total of three gongs at the ceremony, winning for 'Best Rap Performance', 'Best Rap/Sung Collaboration' and 'Best Rap Song' with The Throne collaborator Jay-Z.
Kardashian - who is currently staying in Brazil with West - took to her Twitter page this morning to congratulate her beau on his victory.
"Awww just waking up in Brazil, seeing Kanye won 3 Grammy's last night!!!" she wrote. "That makes a total of 21!!!! That's just so insane! Soooo proud!!!"
Kardashian had revealed last night that she was keeping track of the Grammys online, writing: "In the car heading to carnival here in Rio! Good thing there's all this traffic so you can look up all these hot Grammy looks!"
She singled out Jennifer Lopez - and her controversial leg bombing - for particular praise, saying: "Wow @JLo looks the best hands down!!!!! So sexy!!!"
West and Kardashian were photographed sightseeing in Rio de Janeiro over the weekend, visiting the famous Christ the Redeemer statue and walking around with Will Smith.
They are currently expecting their first child together, although Kardashian is said to be suffering from pains related to the stress of her divorce proceedings with ex-husband Kris Humphries.
Photo gallery - Grammy Awards 2013 winners: