Abstract: This paper systematically compares the rapid one-step method with the ethanol fixation method for the preparation of flow cytometry samples and optimizes the rapid preparation method.Cell cycle samples were prepared by rapid staining with propidium iodide.The test results of this method and ethanol fixation method were compared in parallel.The reliability of the rapid sample preparation method and the influence of sample placement time on the experimental results were evaluated.The experimental results showed that there was no statistically significant difference in the cell ratio and CV value of the cell cycle between the rapid staining method and the ethanol-fixed staining method.There was no significant difference in the percentage of cell cycle phase with in 6-days staining,but CV value and fluorescence intensity were significantly changed.Adding2%~4% serum to the rapid staining solution can effectively reduce the cell viscosity and improve the detection speed of high viscosity samples.