Objective To analyze the reasons causing false positive results of white blood cells (WBC) detected by AVE‐763B automatic urine analyzer .Methods WBC positive samples ,detected by AVE‐763B automatic urine analyzer ,were re‐inspected by microscope .Results In the 740 positive samples ,224 cases were false positive ,the false‐positive rate was 30 .2% ,among which 145 cases could be correctly classified by using image analysis ,and the false‐positive rate reduced to 10 .7% .Conclusion Many fac‐tors could cause false positive results .To improve the accuracy of AVE‐763B urine analyzer ,re‐inspect should be performed .