The traditional measurement method of the sheet polarizer transmission ratio depends on the relative rotation of the polarizers, which is greatly affected by the light source polarization degree and the detector polarization-dependent response, and has a low measurement precision. To solve the above problem, this paper proposes a method based on Stokes vector analysis, by analyzing the polarization states change between the input and output light along with optimization algorithm, to extract the polarization parameters. This method has fast measurement speed, and is universal to the characterization of polarization optical elements used in flat panel display industry.