The men's 400m freestyle events at the 2019 World Para Swimming Championships were held in the London Aquatics Centre at the Queen Elizabeth Olympic Park in London between 9–15 September.

Medalists S6Antonio FantinAndrei GranichkaViacheslav LenskiiS7Mark MalyarAndrii TrusovInaki BasiloffS8Andrei NikolaevRobert GriswoldZhou ZhihuaS9Jacobo Garrido BrunBrenden HallUgo DidierS10Maksym KrypakBas TakkenAlexander ElliotS11Rogier DorsmanUchu TomitaHua DongdongS13Ihar BokiKyrylo GarashchenkoAlex Portal

Results S6

S7

S8

S9

S10

S11

S13

References