Demir Kapija (Macedonian: Демир Капија [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.

[2] Ethnic groups in the municipality include: