Abstract: To investigate the interaction between herbivorous plant bugs and their host plants, a comprehensive survey was conducted from July to September of 2019 in the natural grasslands of Enhe Russian Ethnic Township in Erguna City. This study aimed to elucidate the species diversity and composition of herbivorous plant bugs and their host plants, as well as construct and analyze an interaction network between them. The results reveal that there were 40 species of herbivorous plant bugs belonging to 15 genera distributed in the study area, along with 61 plant species distributed across 50 genera and 22 families. An interaction network was established involving 32 herbivorous plant bug species and 22 host plant specie, which exhibited characteristics of low nestedness and high modularity structure (connectance 0.20, web asymmetry 0.58, nestedness 39.01, modularity 0.49). The species degree of both herbivorous plant bugs and host plants followed a right-skewed pattern, predominantly comprising generalized species. Notably Lygus sibiricus was identified as a keystone species within this network. Through an in-depth analysis of these interactions, we can gain a deeper understanding of the roles and positions of different herbivorous plant bug species within grassland ecosystems. Monitoring the occurrence of key plant bug species can provide valuable insights for maintaining the balance and stability of grassland ecosystems.