The Swimming competition at the 4th Pan American Games was held in São Paulo, Brazil during the Games' run in 1963.

It consisted of 16 long course (50m) events: 8 for males and 8 for females.

[1][2][3][4][5][6][7][8][9][10] In these Games, the U.S. earned all gold medals that were in dispute in swimming.

Venezuela won for the first time a medal, a bronze in the women's 4x100m medley relay.