During the qualification round at the World Championships, Lee helped the USA qualify to the team final in first place, over five points ahead of second place China. Individually, Lee qualified to the all-around final in second place behind teammate Biles despite a fall on the balance beam. She also qualified in second place behind Biles to the floor exercise final, beating out teammate Carey in a tiebreaker, and to the uneven bars final in third place behind reigning World Champion Nina Derwael of Belgium and 2015 World Champion Daria Spiridonova of Russia. Even with the fall on beam, Lee also would have qualified as a reserve for the balance beam finals, but was excluded by the two-per-country rule, as Biles and Eaker had both qualified in higher positions.