|Born||August 14, 1957|
|Strokes||Freestyle, Backstroke and Individual Medley|
Rosario was also a competitor in the Asian Games, first competing in the 1974 Asian Games in Tehran where he won two silvers in the 100-meter and 200-meter back stroke, and three bronzes in the 4x100-meter and 4x200-meter freestyle relays, and the 4x100-meter medley relay. He is also the gold medalist for the 200-meter men's freestyle event of the 1978 Asian Games. He also won two bronzes in the 4x100-meter medley relay and 4x200-meter freestyle relay.
Rosario was elected as corporate secretary of Philippine Swimming, Inc. (PSI; then known as Philippine Amateur Swimming Association or PASA), the governing body of swimming in the Philippines, in 2010. In April 2017, Rosario was designated as Officer in Charge or Acting President of PSI.
- Evans, Hilary; Gjerde, Arild; Heijmans, Jeroen; Mallon, Bill. "Gerardo Rosario". Olympics at Sports-Reference.com. Sports Reference LLC. Archived from the original on 13 January 2012. Retrieved 1 June 2012.
- "2nd Batch of Inductees Philippine Sports Hall of Fame". Philippine Sports Commission. 16 January 2016. Retrieved 1 May 2018.
- Navarro, June (11 April 2017). "Asiad champ takes over swim body". Philippine Daily Inquirer. Retrieved 2 May 2018.
- "Intl swimming coach to retire in Negros - report". GMA News. 7 October 2008. Retrieved 2 May 2018.
- Navarro, June (27 June 2016). "Swimmer Cayco, 16 others inducted into Hall of Fame". Philippine Daily Inquirer. Retrieved 2 May 2018.
- "Rosario named OIC of troubled 'swim' group". Manila Bulletin. 11 April 2017. Retrieved 2 May 2018.