Based on the ecological niche theory, population composition, dynamics, time and niche of rice plant hoppers and main predatory arthropods were investigated using grey relational analysis in three experimental treatment plots. Chemical fertilizer utilization, integrated rice-duck cultivation and no chemical pesticides/fertilizer application. Results indicated that differences in individual numbers, temporal variation characteristics, temporal niche breadth and overlap index for rice plant hoppers and the main predatory arthropods varied among the three treatment plots and the control. The ratio of natural enemy to rice plant hoppers in the integrated rice-duck plot decreased by 1.72% and 26.14%, respectively. Ecological niche breadths for predatory arthropods (except for Coccinellidaein) the rice-duck plot were between 2.14% and 35.77% lower than those under chemical fertilization. Niche overlap indexes for most of the predatory arthropods (such as Tetragnathidae, Staphylinid, Araneidae and Coccinellidae) increased. Rice plant hoppers numbers under rice-duck conditions were 23.70% lower than under chemical fertilization. Grey correlation degrees between the main predatory arthropods and the rice planthopper were distinguished in different rice cropping patterns or groups of predatory arthropods. Coccinellidae, Lycosidae and Theridiidae had the greatest influences on rice planthopper populations in the rice-duck integrated cultivation plot.