Abstract: The optimization of the reversed phase high performance liquid chromatographic separation of six steroids of long acting contraceptives is described. A procedure is used to determine the design space, calculate the coefficients of a seven-term special cubic equation, and modify the model using the optimum experiment. Assisted with the computer, an optimum area could be predicted by overlapping the minimum resolution map with the analysis time map. It is likely that the method described in this paper will provide the basis or the simultaneous optimization of both separation and analysis time and prove to be a useful tool for the optimization of RP-HPLC of known compounds. We firstly utilized the time programming function to improve the detection sensitivities of estrogenic compounds. This method is successfully applied to the analysis of compound megestrol acetate injection and compound hydroxyprogesterone caproate injection. The method is sufficiently simple and rapid yet sensitive and accurate enough for the quality assurance of these types of pharmaceuticals.