Abstract: In order to understand the role of arthropod community's diversity in the management of insect pests, population size of rice planthoppers was correlated to diversity index (H). The population size of rice planthoppers was linearly correlated to diversity index (H) for organic and chemical control paddy fields, with arthropods collected by three methods, sweep net, sucking machine and visual observations. Negative correlation coefficient (r) between diversity index (H) and planthopper population was found for organic paddy fields, significant for sweep net (r=-0.8506) and visual observation (r=-0.8638) sampling methods. Although similar results were recorded for chemical control paddy fields, the correlations were not significant. The results described herein show that the arthropod diversity index can to some extent indicate the population size of rice planthoppers.