For broadening the output voltage range of the power factor correction circuit under the requirement of high power factor and low harmonic distortion rate and achieving the application of the power factor correction circuit in the wider filed，a kind of improved power factor correction circuit with wide output voltage range and its supporting control method are proposed. Firstly，the basic operating principle of the proposed improved power factor correction circuit with wide output voltage range is analyzed；Then，an adaptive duty cycle compensation stage is introduced on the basis of the conventional double-loop control，which not only improves the power factor of the proposed circuit，but also reduces the total harmonic distortion of the proposed circuit；Finally，a set of 3 kW improved power factor corrector prototype is developed to verify the proposed topology and control method. The test results show that the use of the improved power factor correction circuit proposed in this paper can operate at high power factor and low total harmonic distortion rate in the output voltage range of 50~500 V.