Objective To evaluate the significance of positive autoantibodies number in antinuclear antibodies(ANAs) spectrum for the diagnosis of systemic lupus erythematosus(SLE).Methods A total of 1 297 patients were included in this study,among them 148 cases were SLE,317 cases were non-SLE rheumatic diseases,99 cases were nephropathy,210 cases were hematological diseases,and 523 cases were other diseases as the control group.The ANAs level in each group was detected by immunoblotting.The rate comparison adopted the chi square test.The value of positive autoantibodies number in diagnosing SLE was analyzed by receiver operating characteristic(ROC) curve.Results The positive autoantibodies number had good diagnostic value for SLE.The area under the curve was 0.934;the positive rate of autoantibodies(AAbs) in the SLE group was 93.92 ％,which was much higher than that in other groups(P＜0.01).When the number of positive-AAbs was ≥3,the positive likelihood ratio was greater than 10(72.78),showing a very good predictive value for the diagnosis of SLE.Conclusion Three or more kinds of positive-AAbs is highly suggestive of SLE.