The Men's 4x100 Medley Relay swimming event at the 2009 SEA Games was held in December 2009.
Results edit
Final edit
| Place | Lane | Nation | Swimmers | Time | Notes |
|---|---|---|---|---|---|
| 1 |  Indonesia |
Guntur Pratama Putra Indra Gunawan Glenn Victor Sutanto Triady Fauzi Sidiq |
3:41.72 | GR | |
| 2 |  Singapore |
3:44.15 | |||
| 3 |  Philippines |
3:46.32 | |||
| 4 |  Malaysia |
3:48.93 | |||
| 5 |  Thailand |
3:49.45 | |||
| 6 |  Vietnam |
3:51.70 | |||
| 7 |  Laos |
5:03.54 |