| Mahshahr County | |
| Native Name: | Persian: شهرستان ماهشهر |
| Settlement Type: | County |
| Image Map1: | IranKhuzestan-SVG.svg |
| Map Caption1: | Location of Khuzestan province in Iran |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Name1: | Khuzestan |
| Seat Type: | Capital |
| Seat: | Bandar-e Mahshahr |
| Parts Type: | Districts |
| Parts Style: | para |
| P1: | Central |
| P2: | Bandar-e Emam Khomeyni |
| Population As Of: | 2016 |
| Population Total: | 296271 |
| Coordinates: | 30.5167°N 63°W |
| Coordinates Footnotes: | [1] |
| Timezone: | IRST |
| Utc Offset: | +3:30 |
Mahshahr County (Persian: شهرستان ماهشهر) is in Khuzestan province, Iran. Its capital is the city of Bandar-e Mahshahr.[2]
At the time of the 2006 National Census, the county's population was 247,804 in 53,347 households.[3] The following census in 2011 counted 278,037 people in 69,488 households.[4] The 2016 census measured the population of the county as 296,271 in 81,211 households.[5]
Mahshahr County's population history and administrative structure over three consecutive censuses are shown in the following table.
| Administrative Divisions | 2006 | 2011 | 2016 | |
|---|---|---|---|---|
| Central District | 179,804 | 204,646 | 217,186 | |
| 51,358 | 19,730 | 20,884 | ||
| Bandar-e Mahshahr (city) | 109,927 | 153,778 | 162,797 | |
| Chamran (city) | 18,519 | 31,138 | 33,505 | |
| Bandar-e Emam Khomeyni District | 68,000 | 73,391 | 79,085 | |
| 922 | 1,034 | 732 | ||
| Bandar-e Emam Khomeyni (city) | 67,078 | 72,357 | 78,353 | |
| Total | 247,804 | 278,037 | 296,271 | |