Abstract: The objective of this study is to explore the bioinformatics characteristics of the short-chain dehydrogenase/reductase（SDR） gene family and the function of the flowering process. The conserved motifs, chromosome localization, collinearity, evolutionary relationship and cis-acting elements of PmSDR gene family were analyzed by bioinformatics methods, and the expression pattern of PmSDR gene family were explored by combining transcriptome data of different flowering stages and flower organs and fluorescence quantitative PCR. A total of 159 PmSDR gene family members were identified and classified into 4 types and the members of the same subfamily had high conserved motifs. It is not evenly distributed on 8 chromosomes and has a large number of clusters. The interspecific collinearity analysis showed that compared with Prunus armeniaca, Prunus mume and Prunus persica had higher homology of SDR gene family. There are a large number of cis-acting elements involved in plant growth and development, hormone regulation, light response and stress response in the promoter region. Analysis of gene expression patterns showed that: PmSDR gene family are widely expressed in different flowering stages and flower organs, and their expression levels vary greatly. Seven genes, PmSDR114C1, PmSDR114C16, PmSDR108E3, PmSDR108E9, PmSDR108E17 and PmSDR108E19, which were significantly up regulated in the flowering period or had specific high expression in the flower organs, were selected for fluorescence quantitative verification analysis showed that PmSDR114C1 and PmSDR114C16 may be involved in the regulation of flowering period in Prunus mume. PmSDR108E3, PmSDR108E9,PmSDR108E16, PmSDR108E17 and PmSDR108E19 may be involved in the floral synthesis in Prunus mume. This study provides theoretical basis and reference for the function analysis and also provides research basis for the molecular mechanism of PmSDR in the process of blossom.