〔Abstract〕 The Influenza A H1 N1 suspected patients who underwent Influenza A H1 N1 influenza rapid antigen detection and RNA detection were incorporated into this study. All incorporated suspected patients were classified into 3 groups: single positive or negative group(antigen detection negative and RNA detection positive group), both negative group, both positive group. 44 normal persons without any disease who underwent healthy examination at the same time were selected as the control group. Univariate and multivariate analysis of White blood cells(WBC), Neutrophils(NEUT%), Lymphocyte(LYMPH%) and Monocyte(MONO%) were carried out to compare the statistical differences among these four groups. Meanwhile, receiver operating characteristic curves were drawn(ROC curve). The WBC and NEUT% of single positive or negative group were higher than both negative group(bothP<0.05), while the LYMPH% of single positive or negative group was lower than both negative group(P=0.023). There was no difference in these four factors between single positive or negative group and both positive group. The WBC and NEUT% of both negative group were lower than both positive group(bothP<0.05), while the LYMPH% and MONO% of both negative group were higher than both positive group(bothP<0.05). The WBC and NEUT% of single positive or negative group were higher than control group(bothP<0.05), while the LYMPH% of single positive or negative group was lower than control group(P<0.001). The WBC, NEUT% and MONO% of both negative group were higher than control group(bothP<0.05), while the LYMPH% of both negative group was lower than control group(P<0.001). The WBC and NEUT% of both positive group were higher than control group(bothP<0.05), while the LYMPH% and MONO% of both positive group were lower than control group(bothP<0.05). Based on the logistic regression analysis of single positive or negative group and both negative group, only WBC had statistical significance(P=0.010, HR: 1.51, 95%CI: 1.11～2.06). The area under ROC curve(AUC) of WBC in the diagnosis of false negative antigen detection was 0.890(95%CI: 0.79～0.99). The best cutoff value of WBC was 8.5×109/L. If the result of antigen detection is negative but the WBC is greater than or equal to 8.5×109/L, the RNA detection is needed to make the correct diagnosis.