The Women's 100m Butterfly competition of the swimming events at the 1979 Pan American Games took place on 5 July at the Piscina Olimpica Del Escambron in San Juan, Puerto Rico.
[1] The last Pan American Games champion was Camille Wright of US.
[2][3][4][5][6][7] This race consisted of two lengths of the pool, all in butterfly.
[8] All times are in minutes and seconds.
[1] The final was held on July 5.