| Official Name: | Mönsterås |
| Pushpin Map: | Sweden Kalmar#Sweden |
| Subdivision Type: | Country |
| Subdivision Name: | Sweden |
| Subdivision Type3: | Municipality |
| Subdivision Name3: | Mönsterås Municipality |
| Subdivision Type2: | County |
| Subdivision Name2: | Kalmar County |
| Subdivision Type1: | Province |
| Subdivision Name1: | Småland |
| Area Footnotes: | [1] |
| Area Total Km2: | 4.10 |
| Population As Of: | 2020 |
| Population Total: | 5186 |
| Population Density Km2: | 1154 |
| Timezone: | CET |
| Utc Offset: | +1 |
| Timezone Dst: | CEST |
| Utc Offset Dst: | +2 |
| Coordinates: | 57.0333°N 43°W |
Mönsterås (in Swedish pronounced as /mœnstɛrˈoːs/)[2] is a locality and the seat of Mönsterås Municipality, Kalmar County, Sweden, with 6,352 inhabitants in 2012.
Mönsterås is associated with the Swedish poet Carl Boberg, particularly his 1885 writing of the lyrics for the eminent hymn "O Store Gud" (or "How Great Thou Art" by its common English title).