The 26-year-old Oscar-winning actress wore her new engagement ring while hosting Saturday Night Live over the weekend.
Alex, 36, reportedly popped the question during a trip to Tokyo in March, according to Us Weekly.
This is a huge year for Brie after winning the Academy Award for her work in the movie Room. She has spent much of the year in Asia and Australia while working on Kong: Skull Island.
Alex is a musician best known for being the lead singer of the bank Phantom Planet. He got a shout out from Brie during her acceptance speech at the Oscars!