The purpose of this study is to lay a foundation for subsequent studies of antibacterial activity of pathogenesisrelated protein PR10 through exploring the ribonuclease activity of a PR10 gene in Picea asperata. This study cloned the full length of cDNA sequence of a PaPR10 gene using the annual needles of P. asperata as material by RTPCR technique. The specific primers were designed based on the sequence of PaPR10 which was significantly upregulated in response to the infection of spruce needlefalling pathogen (Lophodermium piceae). In addition, the sequence characteristics of the PaPR10 protein were predicted by bioinformatics software. The PaPR10 gene was prokaryotic expressed and purified, and the ribonuclease activity of the purified protein was detected by substrate method. The results showed: (1) the ORF of PaPR10 gene (GenBank accession number: OM743228) was 456 bp, and encoded 151 amino acids with a relative molecular weight of 16.52 kD and a theoretical isoelectric point of 5.73. (2) The PaPR10 protein had no signal peptide, no transmembrane region and was in the cytoplasm. It had a typical conserved domain of pathogenesis related protein Bet_v_1 family, a glycinerich PLoop conserved domain. However, there was a base mutation in the PLoop domain of PaPR10 protein. The results of phylogenetic analysis showed that PaPR10 protein had high similarity with some PR10 proteins in gymnosperms such as Picea crassifolia and some bryophytes. (3) The PaPR10 protein coexisted in the form of soluble and inclusion bodies with the induction of IPTG. In addition, the expression was the best when the final concentration of IPTG was 0.8 mmol/L at 30 ℃ for 10 h, but the purified PaPR10 soluble protein had no ribonuclease activity. The PaPR10 protein does not have ribonuclease activity.