Langenbach bei Kirburg is an Ortsgemeinde – a community belonging to a Verbandsgemeinde – in the Westerwaldkreis in Rhineland-Palatinate, Germany.

The community lies in the Westerwald between Limburg and Siegen on the boundary with North Rhine-Westphalia.

The Langenbach, which belongs to the Sieg drainage basin, flows through the municipal area.

Langenbach bei Kirburg belongs to the Verbandsgemeinde of Bad Marienberg, a kind of collective municipality.

The nearest InterCityExpress stop is the railway station at Montabaur on the Cologne-Frankfurt high-speed rail line.