The actress competed against Fallon on Monday's show to see who could get the most answers right.
The duo took turns trying to identify random Marvel movies after being shown one second of footage.
Johansson was unable to figure out that a group of robbers wearing Avengers masks was from Spider-Man: Homecoming, but then correctly matched clips to Iron Man 2, Avengers: Age of Ultron and Captain Marvel.
Johansson then won the game during a sudden-death round after matching the clip to Avengers: Infinity War first.
"It really is a great movie to see in the theater because it's super cinematic, explosive, loud, fun and passionate," Johansson told Fallon about the film.
Johansson also introduced a new action clip from the film, which featured herself and star Florence Pugh being chased on the rooftops of Budapest, Hungary.