A power amplifier apparatus includes a dither superimposing unit superimposing DC dither on a digital signal; a switching signal generating unit converting the digital signal on which the DC dither is superimposed by the dither superimposing unit to a pair of drive pulses on high and low sides having opposite levels; and a cancel signal generating unit generating a cancel signal to cancel a DC component caused by the DC dither by changing a ratio of pulse widths of the drive pulses on the high and low sides generated by the switching signal generating unit.