The Hessian Main State Archive goes back to the archives of the Nassau territories. After the establishment of the Duchy of Nassau, these were consolidated in the Duchy of Nassau Central Archive in Idstein, which maintained branches in Weilburg and Dillenburg and also took over the records of the secularized monasteries and convents. After the annexation of Nassau by Prussia, the Idstein archive became responsible for the administrative district of Wiesbaden, but with the exclusion of the city of Frankfurt, which retained its own archive. In 1881, the now Prussian State Archive moved to Wiesbaden, where it moved into a new building in Mainzer Straße, which was extended by a side wing in 1908/9.

With the founding of the federal state of Hesse in 1945, the Wiesbaden State Archives became responsible for all central authorities and institutions of the state in addition to its previous area of responsibility. Since 1963, it has therefore been known as the "Hessian Main State Archive". Soon the premises were no longer sufficient to cope with the growing influx of files and to meet the increased user requirements. Even a modest administrative extension in 1963 and a rented temporary storehouse could not solve the problems.

Only a new building erected on Mosbacher Straße in 1981-85 brought the necessary relief. Fully equipped with compact systems and with the volume conversion of all types of archival material into file formats, the stacks, which extend over 9,500 m2 on seven floors, have a storage capacity of around 75,000 linear meters. Of this, 45,000 linear meters of files and official records, 65,000 documents, 170,000 maps, plans and posters as well as 140,000 pictures now occupy over 90%. In addition, there are internal library stacks, a photo, restoration and bookbinding workshop, other function rooms and offices for around 70 staff. The public area has a reading room with adjoining rooms and a lecture hall for 100 people. The spacious entrance hall also serves as an exhibition area. The new archive building has also set new technical standards. This applies not only to the gas-powered automatic extinguishing system, but above all to the artificial air conditioning, whose energy requirements are covered by a combined heat and power plant, which was still new at the time.

At the same time as the new building was occupied, digital information technology was systematically introduced. After initial attempts had already been made at the beginning of the 1970s, all archival activities were now tested for their automation capability and suitability for automation in close cooperation with the Hessian Central Office for Data Processing and implemented in practice in the HADIS project in 1987. It provided for a multifunctional overall solution with networked workstation computers and mainframe connection and assumed a pilot function nationwide. The IT-supported indexing of archival records, the automation of finding aid printouts, online research and, in the next step, the provision of data on the Internet have not only profoundly changed the work of the archivist, but also the working possibilities of the user. No less drastic is the transition from paper-based to digital file management that public authorities have been pursuing since the 1990s and the associated problem of long-term archiving of digital data. In order to meet this challenge, a digital archive with special equipment and personnel was set up at the Hessian Main State Archives in 2009 with responsibility for the whole of Hesse.

The legal basis for the activities of the Main State Archive is the Hessian Archive Act of 18.10.1989 in the version of 5.7.2007. Use is regulated in more detail by the user regulations of 11.3.1997. As a house of history, the archive is open not only to specialist historians but also to all those who can demonstrate a legitimate interest elsewhere, be it research into local or family history, the examination of legal relationships or other historical information requirements. Restrictions arise primarily for reasons of personal privacy and the state of preservation of archive records. In addition to the provision of source material, the Main State Archive is also actively involved in the promotion of regional history. This is done both through its own exhibitions and through close cooperation with the Historical Commission for Nassau and the Association for Nassau Antiquity and Historical Research, which takes place in particular in the editing of publications and the organization of lecture events.