In order to understand better the resistant mechanism of spinach（Spinach oleracea L.）downy mildew and lay foundation for further clone of spinach downy mildew resistance genes and marker-assistedselection of resistance breeding，2 pares of degenerate primers were designed from the conserved motifs of NBSLRR type plant resistance gene．There are 3 types of spinach material-commercial hybrid‘RZ51-147’，inbred line‘12S3’and‘12S4’．Two pares of primers were used for amplifying the disease-resistant gene analog（s RGAs）by polymerase chain reaction（PCR）from the genomic DNA of these 3 material．After cloning and sequencing the PCR products，23 resistance gene analogs with uninterrupted open reading frames（ORFs）and conserved domains of NBS were obtained from spinach，and deposited in GenBank with the accession number of KX914865-KX914887．Homology research showed that most of these 23 RGAs shared high homology with some putative disease-resistant genes or the other relative protein genes in Beta vulqaris．For example，the nucleotides of SP1，
SP2，SP5，SP6，SP10，SP11，SP12，SP13 were over 86% identical to disease resistance protein RF45 from sugar beet，and the nucleotides of SP3，SP4，SP8，SP9，SP24 were over 85% identical to sugar beet disease resistance RPP13 protein．In addition，these 5 RGAs shared 32.20%-33.52% amino acid sequence homology with sunflower downy mildew resistance gene PI8，and clustered a group with PI8 gene in phylogenetic tree，suggesting that these 5 RGAs might be related to downy mildew gene．Homologous evolution analysis demonstrated that all of RGAs were ranked into non-TIR-NBS-LRR type R gene except SP7，which was consistent with the result based on multiple alignment of deduced amino acid sequences．