Abstract: Active Power Factor (PF) correction filter alliterates to ameliorate (PF) and meiosis Total Harmonic Distortion (THD) that play an important role for correction the line current. DC to DC chopper in closed loop system in brought nearer to unity. When therapy the (THD) ratio in the input side this lead to antialiasing the (PF). The analysis and design of the proposed research is carried out using MATLAB/Simulink.