West proposed to Kim, 33, with a 15-carat diamond ring in front of her friends and family at AT&T Park in San Francisco on October 21, reported E! online.
"Last night was truly magical. I am the luckiest girl in the world! I get to marry my best friend," Kim said.
Prior to the proposal, the rapper went to Kim's mother Kris Jenner to ask for her blessing.
He later surprised the socialite as he was on his knee, proposing to her with a Lorraine Schwartz ring. A giant screen on the field flashed sign, 'Please marry me.'
"Saved the best one for the last one! Speechless," he captioned the snap.
Kim also took to Instagram to share a photo of her ring. "Yes!" she wrote.
