George O'Malley dies in season 6 of Grey's Anatomy. His death occurs in the very first episode of the season, titled "Good Mourning," which aired on September 24, 2009. George dies due to complications from injuries sustained after he heroically jumped in front of a bus to save a woman’s life. His brain swells fatally during surgery, and his death is a significant and emotional event for the characters on the show
. In contrast, if you were referring to George Cooper from Young Sheldon, he dies in season 7, episode 12 of that series, due to a heart attack
