Dry reference collections of plants and fungi serve as essential repositories of the global flora and funga diversity, preserving specimens that provide critical data for scientific research, environmental monitoring, and conservation. By maintaining accurate records of species distribution and diversity, herbaria and fungaria contribute to understanding ecosystem dynamics and to guiding sustainable management of natural resources worldwide. This study presents a comprehensive assessment of Cercospora species in Azerbaijan based on dry specimens collected over various periods and preserved in the fungarium (BAK), together with a review of published records from the country. Studied specimens were examined for conidiophores and conidia morphological characters, allowing accurate species identification within the genus and their names alignment with current speciesomic revisions and novelties. As a result of this work, 18 species of Cercospora are currently listed for Azerbaijan in the fungarium. These species are associated with 20 host plant species representing 17 genera, 13 families, and 12 orders. Most of the fungi invaded predominantly different weed plants. The highest number of fungal species occurred on hosts from the families Fabaceae (C. rautensis, C. traversoana, C. zebrina, C. zonata) and Malvaceae (C. althaeina, C. malvarum, C. malvicola), whereas Cercospora invading other plant families was represented by only one fungal species in each. Analysis of Cercospora species distribution revealed that most fungal specimens were collected in the Greater Caucasus and the Nakhchivan mountain regions, with five species found in each region.