The Hungarian National Infrasound Network (HNIN) is a permanent infrasound network operated by the Kövesligethy Radó Seismological Observatory (Geodetic and Geophysical Institute, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences). The main purpose of the network is the continuous monitoring of seismo-acoustic events in Hungary and to provide high quality data for the seismological and geodynamic scientific research. The first infrasound array of the HNIN started its operation in 2017. Currently the network consists of one four-element array equipped with microbarographs. The PSZI infrasound array is co-located with a seismic three-component broadband station, PSZ, operated by the Hungarian National Seismological Network (HNSN). All data are acquired in real-time to the HNIN data centre located at the Kövesligethy Radó Seismological Observatory in Budapest that also operates HNSN. The HNSN/HNIN follows an open data policy, as seismic and infrasound waveform data are available in real time without any restriction within from the HNSN/HNIN data centre as well as from the European Integrated Data Archive via the GEOFON data centre.