The holdings of the majority of old and rich libraries include manuscripts that had been processed in a similar manner as printed books. The situation at archival libraries is however different: at their central unit – the archives, there is a significant amount of archival manuscript materials and documents resembling manuscripts that are processed in the archival manner. This paper describes and catalogues the manuscripts from the Library of the State Archives in Zadar, which is of interest to users of both archival and library materials. This library was established by the Dalmatian Government in 1894 and joined to the Government Archives, established in 1624. It subsequently became the Archival Library; currently, it represents one of the departments of the Archives, and belongs to bigger archival libraries in Croatia. In the course of time, it became one of the most important research libraries for studying the history of Dalmatia and the archival materials relating to the historical area of Dalmatia from Rab to Kotor in the period ranging from the 10th to the 20th centuries. The Library includes 50 000 volumes of library materials: books; brochures; journals and newspapers; manuscripts and dissertations. The Library began receiving manuscripts from its earliest days, by the means of transfer from government departments (mainly from the Presidency, the Registry Office and the Old Archives), purchase and donations. After 1950, the manuscripts were separated from the printed library holdings and formed into a separate collection, which was subsequently enriched. Currently, the Library includes 130 titles in 153 volumes of manuscripts dating from the period between the 16th and the 20th centuries, and in the majority of cases referring to the history of Dalmatia. These are mainly original and attributed works, transcripts, translations, discussions, chronicles, genealogies, reprints from other archives, as well as historical, archaeological and literary works, etc. The majority of them are originals, and the rest are transcripts dated between the 17th and the 20th centuries. The paper explores the historical background and the development of the collection; it further analyses the availability of information and the relevance of the manuscript processing method within the system of library and archival informational operation. The annex offers a catalogue of the manuscripts processed in accord with the regulations for developing alphabetic catalogues and the standards for bibliographic description of old (antiquary) publications and manuscripts, as well as with the universal international standard for describing archival materials and the international standard for making archival standardised entries (for legal entities, natural persons, and families).