As a result of the long-term monitoring of the insect fauna of Yeongsil in Hallasan Mountain National Park, Jeju Island, a total of 146 species belonging to 52 families in 10 orders were identified and enumerated, with the exception of Lepidoptera. In terms of the species observed, 74 Coleoptera species (50.68%) were observed, followed by 17 Hemiptera species (11.70%), 16 Homoptera species (10.95%), 12 Hymenoptera species (8.21%), 11 Orthoptera species (7.53%), 8 Diptera species (5.47%), 5 Odonata species (3.42%), and 1 species each of families Neuroptera, Phasmatodea and Mecoptera (0.68%). The composition of species number of each order was comparative to that of Jeju Island. These results may reflect that the natural environment of Yeongsil area is relatively specific on this island and well conserved.