The research of diurnal butterflies' fauna on the south-east area near Karlovac lasted since 2001 till 2007. The research of abundance has been done during 2006 and 2007. Four linked, but ecologically different sites were chosen, where the fauna of diurnal butterflies and number of individuals of all diurnal butterflies was detemined, according to transect method. Data analysis included making of tabulations and diagrams of butterflies abundance just as a comparison of sites with Sørensen’s similarity coefficient. There has been analysed the differences in abundance of butterflies regarding to ecological site conditions. Changing of abundance of each family, just as five most numerous species, has been analysed during 2006 and 2007. The influence of average daily temperatures and amplitudes on changing of abundance was considered. In total, 65 species were found on research area. It represents 34.21% of Croatian diurnal butterfly species. According to zoogeographical categories the most species were founded to be eurosiberian. The biggest abundance and biodiversity was established on site that includes the forest margin. The effect of temperature on abundance of families and most numerous species did not take noticeably significance during the summer. The temperature changes are not only factor that controls the abundance of individulas of some species. More significant factors are types of species (characteristics of butterfly fauna) and individual species biology.