LC filters are connected both input and output side of the AC chopper circuit in order to remove the switching ripple and harmonics. Characteristics of THD and input-power-factor are examined by simulation and experiments. When the load is resistive, characteristics are little influenced by the filters. In case of the inductive load, since two poles exist owing to the input and output filters, waveform distortion becomes large. It is shown that THD can be improved by reducing input filter capacitance.