The invention discloses a method for detecting an
antigen expression level by using a
flow cytometry. The method comprises the steps of firstly, carrying out immunofluorescent
staining on a target
cell, then detecting the stained
cell by adopting the
flow cytometry and carrying out data calculation and analysis, wherein when the parameter of the low
cytometry is set, the resolution of a
fluorescence channel to be detected is reduced; and obtaining a geometric average
fluorescence intensity of an
isotype control or a negative
cell and a target cell to-be-detected
antigen, figuring out respective geometric average
fluorescence intensity rates with the geometric average
fluorescence intensity rate of the
isotype control or negative cell as a critical value, and if the geometric average
fluorescence intensity rate of the target cell to-be-detected
antigen is higher than that of the
isotype control or negative cell by a preset value, the expression of the target cell to-be-detected antigen is achieved. According to the invention, the accuracy and the precision of target
cell determination are effectively increased, experimental errors and subjective judgment errors of weak antigen expression are maximally reduced, and the
flow cytometry is effectively promoted to be applied to multiple fields.