Altenkirchen 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 district was established in 1816 by the Prussian administration. It combined the county of Wildenburg and the two counties of Sayn. The former had been part of Berg, the latter ones had belonged to the duchy of Nassau.