| Demir Kapija Municipality | |
| Native Name: | Општина Демир Капија |
| Native Name Lang: | mk |
| Settlement Type: | Urban municipality |
| Subdivision Type: | Country |
| Subdivision Type1: | Region |
| Subdivision Name1: | Vardar |
| Flag Size: | 160px |
| Shield Alt: | Coat of arms of Demir Kapija |
| Coordinates: | 41.409°N 22.244°W |
| Seat Type: | Municipal seat |
| Seat: | Demir Kapija |
| Leader Title: | Mayor |
| Leader Name: | Lazar Petrov (SDSM) |
| Elevation M: | 202 |
| Area Total Km2: | 311.06 |
| Population Total: | 3,777 |
| Population Density Km2: | auto |
| Registration Plate: | DK |
| Timezone: | CET |
| Utc Offset: | +1 |
| Postal Code Type: | Postal Code |
| Postal Code: | 1442 |
| Area Code Type: | Area Code |
| Area Code: | 034 |
Demir Kapija (Macedonian: Демир Капија in Macedonian pronounced as /ˌdɛmir ˈkapija/) is a municipality in southern part of North Macedonia. Demir Kapija, which means "iron door" or "iron gate" in Turkish, is also the name of the town where the municipal seat is found. Demir Kapija Municipality is part of the Vardar Statistical Region.
The Došnica river which springs from Mount Kožuf is the source of drinking water and hydroelectric power production (at Čiflik) for the municipality.[1]
The municipality borders
According to the last national census from 2021 this municipality has 3,777 inhabitants.
Ethnic groups in the municipality include:
| 2002 | 2021 | ||||
| Number | % | Number | % | ||
| TOTAL | 4,545 | 100 | 3,777 | 100 | |
| Macedonians | 3,997 | 87.9 | 3,076 | 81.44 | |
| Turks | 344 | 7.6 | 376 | 9.95 | |
| Serbs | 132 | 2.9 | 130 | 3.44 | |
| others | 72 | 1.6 | 80 | 2.12 | |
| Persons for whom data are taken from administrative sources | n/a | n/a | 115 | 3.04 | |
Populated settlements include: