| Jämijärvi | |
| Official Name: | Finnish: Jämijärven kunta Swedish: Jämijärvi kommun |
| Settlement Type: | Municipality |
| Coordinates: | 61.8167°N 63.5°W |
| Subdivision Type: | Country |
| Subdivision Name: |  Finland |
| Subdivision Type1: | Region |
| Subdivision Name1: | Satakunta |
| Subdivision Type2: | Sub-region |
| Subdivision Name2: | Northern Satakunta sub-region |
| Leader Title: | Municipal manager |
| Leader Name: | Aku Autio |
| Established Title: | Charter |
| Established Date: | 1865 |
| Blank3 Name: | Climate |
| Blank3 Info: | Dfc |
| Timezone: | EET |
| Utc Offset: | +02:00 |
| Timezone Dst: | EEST |
| Utc Offset Dst: | +03:00 |
| Website: | www.jamijarvi.fi |
Jämijärvi is a municipality of Finland.
It is located in the province of Western Finland and is part of the Satakunta region. The municipality has a population of and covers an area of NaNJämijärvi}} of which NaNJämijärvi}} is water. The population density is NaNJämijärvi.
The municipality is unilingually Finnish.
Jämijärvi Airfield is one of the busiest general aviation airfields in Finland. A serious aviation accident happened in Jämijärvi in April 2014.