In our study we surveyed the butterfly diveristy on selected grasslands in the Municipality of Domžale. In order to achieve this, we carried out eight field surveys at each of the 14 locations between the end of April and the end of August. A total of 49 different butterfly species of which six are listed as endangered in Slovenia. Predominantly widespread and common species in Slovenia and Europe were observed in the Municipality of DomžaleWe can atribute that to various factors, among which the most important is the intensification of agriculture, which is particularly pronounced in the flatter parts of the Municipality of Domžale. The intensified grasslands are characterised by lower butterfly diversity, absence of habitat specialists and orchids which are also important indicators of the quality of the grasslands. We found orchids at eight locations in our study. The most frequent was Anacamptis morio, while Neotinea tridentata was much rarer. We calculated nature conservation value of each location based on butterfly and orchid diversity, with added weight for the presence of protected or endangered species. We also studied the effect of different biotic and abiotic factors on the butterfly diversity. We determined that the locations of the highest nature conservation importance congregate in the hillier part of the manucipality ie. in Dobovlje, Vinje, and in Brdo pri Ihanu. With the exception of the grassland in Vinje, the grasslands are part of the protected area of the Revolutionary Tradition Memorial Park of the Domžale municipality, where environmental changes are already limited. However, the most important nature conservation area is in the plain, at Zaboršt near Domžale. This is one of the last remining humid meadows with orchids in the flatter part. In order to conserve the rare and endangered extensive grasslands in the Domžale municipality and their biodiversity, changes in grassland mangment must be applied, especially concerning the limitations regarding fertilization and mowing of the meadows before the end of flowering season.