To assess the effects of microbial fertilizers on insect and spider communities in tea garden, the occurrence of insects and spiders in tea gardens treated with chemical fertilizers alone(control), with microbial fertilizers alone and with compound fertilizers alone(organic fertilizers mixed with chemical fertilizers) were comparatively investigated. The dominant taxa in insect and spider communities in each treatment were statistically analyzed, and the population growth and decline of the main pests, Matsumurasca onukii, was also analyzed. The results showed that the diversity index and evenness index of the insect and spider communities in the tea garden treated with microbial fertilizer were 2.07 and 0.45, respectively, which were significantly higher than those of the compound fertilizer and chemical fertilizer treatment groups, indicating the structure of the insect community in the tea garden treated with microbial fertilizer was more complex, the ecosystem was rich in species, and the stability was better; the value of dominance concentration index and dominance degree of the insect community in the tea garden treated with microbial fertilizer were the smallest, which were 0.31 and 0.55, respectively, indicating its species were the most abundant and the most stable. The single application of microbial fertilizer has a significant effect on controlling the population size of Matsumurasca onukii in the tea garden. The application of microbial fertilizer can significantly affect the community structure of insects and spiders in the tea garden, reduce the population size of Matsumurasca onukii; and after microbial fertilizer treatment, the structure of insects and spiders in the tea garden is more complex, the ecosystem is rich in species, and the community is in a stable state.