Biodiversity-Productivity relationship is of high interest among ecologists. However, this relationship has been considered mainly within primary producers, and the biodiversity-productivity relationship between different trophic levels has not been well investigated. Biomass, rather than diversity of primary producers may have higher impact on the biomass and diversity of consumers, but these paths are mixed up by the general trend that higher biomass of the producers is associated with their higher diversity. In order to reveal how diversity and biomass of primary producer (aquatic plants) affect those of consumers (Odonata larvae), we analyzed the data set obtained from 64 irrigation ponds. Using path analysis, the path to diversity/biomass of Odonata larvae from plant diversity was separated from that from plant biomass. The results were then compared among different growth forms of aquatic plants (submerged, floating-leaved, and emergent), and the relative importance of paths were discussed.