Objective:To breed and identify the offspring of positive miR-15a/16-1 gene knockout mice and analysis of their splenic cellular immune function. Methods:MiR-15a/16-1 knockout mice were paired in different ways. Genomic DNA was isolated from tails and analyzed by PCR. Complete blood analysis was performed in the blood which was collected from the orbit of mice. Analysis of cellular immune function in spleen was performed in miR-15a/16-1 gene knockout mice by FCM. Results:The positive rate with miR-15a/16-1 gene of filial generation mice met Mendelian genetic law. Compare with wild-type mice,CD19+ and NKG2D+ cells of spleen in miR-15a/16-1 gene knockout mice were all up-regulated expression detected by FCM,although there were not significant changes of frequencies of other surface markers. Complete blood analysis showed that lymphocytes increased. Conclusion:PCR methods can be used to identify the genotype of the miR-15a/16-1-/- mice,and to establish an animal experimental model to further study the important role of miR-15a/16-1. CD19+ and NKG2D+ cells of spleen in miR-15a/16-1 gene knockout mice were increased.