Understanding the impact of biodiversity on ecosystem function and stability is crucial for developing effective conservation and management strategies. However, relationships of biodiversity with community productivity and stability are still controversial. Here, we investigated how the biodiversity indices were correlated with the secondary productivity and stability of benthic macroinvertebrate communities in the Poyang Lake wetland. Thirty sites were sampled in the Poyang Lake wetland for obtaining benthic macroinvertebrate community data in the autumn of 2019. Twelve biological indices representing taxonomic, phylogenetic and functional diversity, as well as indices of the secondary productivity and community stability, were calculated for each sample site. We first investigated the relationships of secondary productivity and community stability with single biodiversity indices by using generalized additive models (GAMs). Then, we quantified the explanatory power of taxonomic, phylogenetic and functional diversity on secondary productivity and community stability. Biodiversity indices totally explained 81.9% and 54.8% of the variation in secondary productivity and community stability, respectively. Functional diversity had the strongest explanatory power on secondary productivity (r²=0.75), while taxonomic diversity had the highest predictive ability on community stability (r²=0.37). Secondary productivity showed significant and negative relationships with taxonomic indices (including Simpson's diversity index, Shannon's diversity index, and Pielou's evenness index), taxonomic diversity, average taxonomic distinctness and functional richness index, which was contrast with previous findings. Among them, Pielou's evenness index had the highest correlation with secondary productivity (r²=0.33). Community stability (calculated as the ratio of second productivity to community biomass) had significant and positive relationships with Simpson's diversity index, Shannon's diversity index, Margalef's richness index, functional evenness index and functional richness index, among which functional richness index had the highest correlation (r²=0.22). Taxonomic, phylogenetic and functional diversity hadsignificant correlations with secondary productivity and community stability, whereas their effects might vary depending on the specific biological communities. Our results can provide valuable insights and guidance for the protection of benthic biodiversity in the Poyang Lake wetland.