The Men's 400m athletics events for the 2020 Summer Paralympics took place at the Tokyo National Stadium from August 27 to September 4, 2021.

The final in this classification took place on 2 September 2021, at 9:42:[4] The T13 category is for athletes with a moderate visual impairment.

Athletes in this category have a variety of visual impairments, but can typically recognize contours from a distance of 2 to 6 metres.

The final in this classification took place on 31 August 2021, at 19:11:[6] The T36 category is for ambulant athletes with cerebral palsy.

The final in this classification took place on 31 August 2021, at 19:31:[9] The T47 category is for athletes who have a single below elbow or wrist amputation or similar disability, with normal function in both legs.

Pushing power comes from elbow extensions, and appears close to normal except for use of modified gloves to compensate for grip.