The direct and the indlrect fluorescent labeling are two different staining methods in immunofluorescent measurement.In flow cytometer measurement,in general,the direct labeling has little nonspecific binding and disturbance,and the experiment data is easy to process.However,because of the magnifying function,the indirect labeling has much nonspecific binding and serous disturbance. It is difficult to distinguish the specific signals from non-specific ones,it is easy to cause confusion in data processing. By comparing samples，the direct labeling is suggested better than the indirect labeling in flow cytometer measurement.