Swimming at the 2009 World Aquatics Championships – Men's 100 metre butterfly
|Men's 100 metre butterfly
at the 2009 FINA World Championships
|Dates||31 July 2009 (heats, semifinals)
1 August 2009 (final)
|Winning time||49.82 seconds|
|Open water swimming|
The men's 100 metre butterfly event at the 2009 World Aquatics Championships took place between 31 July – 1 August at the Foro Italico. Both the heats and semifinals were held on 31 July with the heats being held in the morning session and the semifinals being held in the evening session. The final was held on 1 August.
Prior to this competition, the existing world and competition records were as follows.
|World record||Michael Phelps||United States||50.22||Indianapolis||9 July 2009|
|Championship record||Ian Crocker||United States||50.40||Montreal||30 July 2005|
The following records were established during the competition:
|July 31||Semifinal||Milorad Čavić||Serbia||50.01||WR||CR|
|August 1||Final||Michael Phelps||United States||49.82||WR||CR|
|2||Michael Phelps||United States||50.48||1||4|
|8||Tyler McGill||United States||51.07||2||5|
|13||Michael Rock||Great Britain||51.41||1||1||NR|
|16||Corney Swanepoel||New Zealand||51.79||2||8|
|5||Michael Phelps||United States||49.82||WR|
|7||8||Tyler McGill||United States||51.42|
- Worlds 2009 results: Men's 100m butterfly Heats, from OmegaTiming.com (official timer of the 2009 Worlds); retrieved 2009-08-06.
- Worlds 2009 results: Men's 100m butterfly Semifinals, from OmegaTiming.com (official timer of the 2009 Worlds); retrieved 2009-08-06.
- Worlds 2009 results: Men's 100m butterfly Finals, from OmegaTiming.com (official timer of the 2009 Worlds); retrieved 2009-08-06.