Nematodes are considered major pests in agriculture.In recent years,overdose usage of chemical pesticides causes environmental damages and becomes a thread to food safety.Biological control of nematodes is now of great interests.Nematode-trapping fungi can develop various trapping devices to capture nematodes,making them natural enemies of nematodes in nature,and provide massive resources to development of bio-control agents.We firstly carried out the genomic study on Arthrobotrys oligospora,a model nematode-trapping fungi that can develop adhesive networks on induction of nematodes.Genomic research revealed the lack of repetitive sequences in genome and suggested that RIP mechanism may be responsible.Gene family analysis showed significant expansion of a few protein coding genes,including subtilisin,PKS and NRPS,etc.Proteomics analysis showed that multiple biological processes have been involved in trap formation,including energy metabolism-related pathways,cell proliferation and signal transduction,etc.In addition,we also sequenced the genomes of a few other nematode-trapping fungi that develop various trapping devices,including adhesive branches,adhesive knobs and constricting-rings.Phylogenomic analysis showed that they can be categorized into two major groups,including active mechanic rings and passive adhesive structures.Evolutionary analysis revealed a simplification of the trapping structures of the nematode-trapping fungi.In consistent with gene family analysis,transcriptomic analysis revealed significant regulation of certain genes,including signal transduction and proteolysis-related genes.The significant gene expansion and their significant regulation during trap induction provide hints for their carnivorous adaptation.Furthermore,we investigated the RNAi-related genes in the genome of Arthrobotrys oligospora.We also confirmed the presence of microRNA like RNAs and showed that they play an important role in trap formation.These studies provide new insights into the mechanism underlying trap induction of nematode-trapping fungi and also provide bases for development of efficient bio-control agents.