This study was done to develop environmental risk assessments and a biosafety guide for insect-resistant genetically modified rice at a LMO (Living Modified Organism) isolation field. In the LMO quarantine area of Kyungpook National University, the species diversities and population densities of non-target insects found on insect-resistant genetically modified rice (Bt-T) resistant to Cnaphalocrocis medinalis and on non-GM rices (Dongjin-byeo and Ilmi-byeo) were investigated. The Bt-T event was therefore evaluated under field conditions to detect possible impacts on the above ground insects and spiders. The study compared transgenic rice and two non-GM reference rices, Dongjinbyeo and Ilmi-byeo, at Gunwi in Southern Korea in 2016 and 2017. A total of 9,552 individuals from 51 families and 11 orders were collected from the LMO isolation field. In the three types of rice fields, a total of 3,042 individuals from the Bt-T, 3,213 individuals from the Dongjin-byeo, and 3,297 individuals from the Ilmi-byeo were collected, respectively. There was no difference between the population densities of the non-target insect pests, natural enemies and other insects on the Bt-T and non-GM rices. The data of insect species population densities were subjected to principal component analysis (PCA), which not distinguished among the three varieties, GM and non-GM, reference cultivar in all cultivation years. However, PCA results were clearly separated the samples based on the cultivation years. These results suggest that insect species diversities and population densities during plants cultivation are determined by environmental factors (growing condition and seasons) rather than by genetic factors.