The Men's 100 metres T46 event at the 2012 Summer Paralympics took place at the London Olympic Stadium on 6 September.

[1] The T46 category is for athletes who have a single above or below elbow amputation or similar disability, with normal function in both legs.

There being no event for T45 competitors - double arm amputees - two such athletes took part in this event, and one of them, Zhao Xu of China, took the gold medal.

Prior to the competition, the existing World and Paralympic records were as follows.

rule: first 2 in each heat (Q) plus the 2 fastest other times (q) qualified.