The men's 100 metre breaststroke competition of the swimming events at the 2011 Pan American Games took place on October 16 at the Scotiabank Aquatics Center in Mexico.

[1] The defending Pan American Games champion was Scott Dickens of Canada.

This race consisted of two lengths of the pool, both being in breaststroke.

[2] Prior to this competition, the existing world and Pan American Games records were as follows: Each National Olympic Committee (NOC) was able to enter up to two entrants providing they had met the A standard (1:04.7) in the qualifying period (January 1, 2010 to September 4, 2011).

NOCs were also permitted to enter one athlete providing they had met the B standard (1:06.6) in the same qualifying period.