At the 2021 World Championships in March, Mishina/Galliamov skated both of their programs cleanly to earn new personal bests in both individual segments, as well as overall. In the short program, the team ranked third behind training-mates Boikova/Kozlovskii in first and Chinese team Sui/Han in second, but in the free skate overtook the two leading teams to win the segment and claim the title unexpectedly. Mishina/Galliamov are the first team to win gold in their Worlds debut since Gordeeva/Grinkov of the Soviet Union in 1986, and the second-youngest pair to win Worlds after Gordeeva/Grinkov. They the concluded the season at the 2021 World Team Trophy, where they easily placed first in both segments to help Team Russia win the gold medal.