Abstract: 【Objective】Genome-wide identification and expression analysis of NBS-LRR disease-resistantgenes in cultivated tomatoand its wild relatives were performed, to provide a theoretical basis for the research on the function of NBSLRR disease-resistant genes and the application in plant disease resistance breeding.【Method】NBS-LRR disease-resistant gene family members were identified and analysed on classification, sequence characteristics, chromosome location, phylogeny, and expression patterns under biotic stresses from cultivated(Solanum lycopersicum) and two wild(S. pennellii and S. pimpinellifolium) tomato species genomes using bioinformatics and comparative genomics methods.【Result】In total, 238, 202 and 217 NBS-LRR disease-resistant genes were identified in cultivated tomato and S. pennellii and S. pimpinellifolium genomes, respectively. Based on the differences in the domains encoded by these disease-resistant genes, they were divided into eight types, which were TNL(TIR-NBS-LRR), CNL(CC-NBS-LRR), RNL(RPW8-NBS-LRR), TN (TIR-NBS), CN (CC-NBS), RN (RPW8-NBS), NL (NBS-LRR) and N (NBS), with 58 TNL, 87 CNL and 13 RNL genes, respectively. NBS-LRR disease-resistant genes were weakly acidic in general, and were unstable and hydrophilic, with serine(Ser) phosphorylation and secondary structure of alpha-helix and random coil, which were mainly located in the nucleus, cytoplasm and chloroplast. Chromosome localization revealed that the NBS-LRR disease-resistant genes in cultivated tomato and S. pennellii genomes were unevenly distributed on 13 different chromosomes(virtual chromosome 0-chromosome12), with 58.47% and 52.48% genes forming multiple gene clusters, 35.59% and 22.77% genes forming tandem duplicates, respectively. Systematic clustering divided 477 NBS-LRR disease-resistant genes in the three genomes into ten groups, the N-terminal TIR-type genes were basically clustered together, but CC- and RPW8-type genes were not well separated and clustered in multiple groups;NL- and N-type genes were scattered in various groups. Gene homology analysis revealed 115 pairs of orthologous genes and 8 pairs of paralogous genes in 477 NBS-LRR disease-resistantgenes, equivalent to 51.57% of NBS-LRR genes had a homologous gene, and that they were mainly distributed on chromosomes 4 and 5, with most Ka/Ks values being less than 1, indicating that purification selection had occurred in evolution. It revealed that the most NBS-LRR disease-resistant genes could respond to different bacterial stresses by transcriptome sequencing(RNA-seq) data analysis.【Conclusion】The tomato NBS-LRR disease-resistant genes exist in cluster. During the evolution, a large number of homologous genes have appeared through gene expansion. Also, they can respond to a variety of bacterial stresses.