Altenkirchen (German pronunciation: [ˈaltn̩ˌkɪʁçn̩] ⓘ) is a district in Rhineland-Palatinate, Germany.

It is bounded by (from the north and clockwise) the North Rhine-Westphalian districts Rhein-Sieg, Oberbergischer Kreis, Olpe and Siegen-Wittgenstein, and the districts of Westerwaldkreis and Neuwied.

The history of the district is linked with the Westerwald region.

The county used to be divided into nine mayoralties, including the Bürgermeisterei Weyerbusch.

The valley of the river Sieg borders the Westerwald on the north.