Abstract: In order to provide a rationale and study for the aroma metabolism mechanism of pear fruit, which was PsLOX, the lipoxygenase gene of Korla pear(Pyrus sinkiangensis Yü. ‘Korla xiangli’) was cloned, the expression profiles of PsLOX were monitored in different periods of fruit development. As materials in leaves and fruit of Korla pear at different periods, total RNA was extracted by using the reagent kit, cDNA sequence of target gene PsLOX was obtained by RT-PCR. The function of PsLOX was predicted by bioinformatics, the expression characteristics and differences of this gene were analyzed using semi quantitative RT-PCR(SqRT-PCR) technology with leaves and peel of Korla pear in period of growth and shelf-life. The CDS sequence of PsLOX gene was 912 bp length, coded a predicted protein of 303 amino acids. By bioinformatics, PsLOX gene belongs to the lipoxygenase family. We compared with other plant LOX genes, the amino acid sequence had high homology, and the highest homology with Nanguo pear reached 99%. There was significant difference in the expression of PsLOX gene in development period of pear fruit, which was very low level in the expression quantity at growth development prophase of young fruit, and was the highest value in mature to ripe period, then expression quantity began to decrease. The PsLOX gene was homologously cloned, which were speculated to play a crucial role in aroma metabolism process of Korla pear fruit.