Faunistic research in protected areas is of greatest interest since these are the most unique places in the region. Many of these are islands of minimal anthropogenic impact, such as the Mordovia State Nature Reserve (Russian Federation), founded in 1936. The purpose of the publication of the basis of faunistic research - occurrences of species, is availability of factual information to a broad range of researchers and its implication in research on a wider scale.For the first time, a total of 7,606 records of Lepidoptera occurrences from the Mordovia State Nature Reserve with coordinates have been published as a dataset. It is necessary to embed them in the Global Biodiversity Information Facility (GBIF) in order to make them accessible to everyone. As a result of research from 2007 to 2021, more than 600 taxa were identified for the first time for the territory of Mordovia State Nature Reserve, including more than 450 species for the Republic of Mordovia, four species for the Middle Volga Region and eight species for the Middle and Lower Volga Region.