The population dynamics of insect pests and natural enemies and on triple cropping pattern of rice in Thoi Lai district, Can Tho city were recorded from analysis of indicators of arthropod diversity showed that the 2013 spring - summer crop season consist of the highest species with 71 species and the .lowest were 64 species in the 2012-2013 winter - spring crop season. While the Shannon Weiner index were the highest (3.05) in the autumn crop, that of winter - spring crop were 2.96 and the 2013 spring - summer crop were the lowest (1.82). The dominant species index hold the highest in winter - spring crop (0.19) and they tend to decrease towards the next crop, the lowest were autumn crop (0.13). This dominant was likely to decrease the level of species richness also tended to accumulate for the next crop. Pest control measures by chemical pesticides has reduced insect biodiversity. It is one of the most important causes leading to the less stable and sustainable control measures for chemicals. Sustainable agricultural development is now manipulating for protecting, maintaining and enhancing biodiversity.