The Men's 100 Butterfly swimming event at the 2009 SEA Games was held on December 11, 2009.
Results
editFinal
edit| Place | Swimmer | Nation | Time | Notes |
|---|---|---|---|---|
| 1 | Daniel Bego |  Malaysia |
53.82 | GR |
| 2 | Donny Utomo |  Indonesia |
55.53 | |
| 3 | Quy Phuoc Hoang |  Vietnam |
55.65 | |
| 4 | Thai Nguyen Vo | Vietnam |
55.77 | |
| 5 | James Walsh |  Philippines |
56.16 | |
| 6 | Chatmongkon N |  Thailand |
56.21 | |
| 7 | Kevin Lim | Malaysia |
56.87 | |
| 8 | Jessie Lacuna | Philippines |
59.43 |
Preliminary heats
edit| Rank | Heat | Swimmer | Nation | Time | Notes |
|---|---|---|---|---|---|
| 1 | H2 | Chatmongkon N | Thailand |
55.87 | Q |
| 2 | H2 | James Walsh | Philippines |
56.63 | Q |
| 3 | H1 | Donny Utomo | Indonesia |
56.74 | Q |
| 4 | H1 | Thai Nguyen Vo | Vietnam |
56.76 | Q |
| 5 | H2 | Daniel Bego | Malaysia |
57.04 | Q |
| 6 | H2 | Quy Phuoc Hoang | Vietnam |
57.66 | Q |
| 7 | H1 | Kevin Lim | Malaysia |
58.52 | Q |
| 8 | H2 | Jessie Lacuna | Philippines |
58.87 | Q |
| 9 | H1 | Zaw Phyo Aung |  Myanmar |
1:03.26 | |
| 10 | H1 | Glenn Victor | Indonesia |
1:09.41 | |
| 11 | H2 | Kun Narak |  Cambodia |
1:12.88 | |
| 12 | H1 | T Thepphitack |  Laos |
1:23.08 |