Objective To establish paired box gene 2(Pax2) gene knockout mice by clusterd regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9 (Cas9) technology with double nicking method  so as to provide an animal model for studying the role of Pax2 gene in multiple development.  Methods The sgRNA was designed according to the Pax2 gene sequence, and the designed sgRNA and Cas9 were microinjected into the fertilized eggs of C57BL/6J mice in vitro. F0 generation mice were genetically sequenced to identify genotypes after birth, and a total of 8 F0 generation mice were obtained. The F0 mice were mated with wild C57BL/6J mice to obtain F1 mice, and the mice successfully knocked out were successfully mated with C57BL/6J mice to obtain stable Pax2 knockout mice.   Results The stably propagated Pax2 heterozygous knockout mice were successfully obtained, and the Pax2 gene was deleted by 1628 bp. HE staining showed that the number of glomeruli in knockout mice was significantly reduced. Western blotting result  showed that the expression of Pax2 protein in renal cortex of knockout mice was reduced compared with that in wild type mice.  Conclusion The Pax2 heterozygous knockout mice can be successfully constructed by using CRISPR/Cas9 technology, which lays a foundation for further study of the role of Pax2 gene.