There is provided a power conversion device capable of eliminating a disadvantage of a sharp temperature rise in a switching element by using a discontinuous modulation method. The power conversion device includes a phase voltage command operation unit 33 which calculates a sinusoidal modulation voltage command value to be applied to a motor 8, an inter-line modulation operation unit 34 which, based on the sinusoidal modulation voltage command value, calculates a discontinuous modulation voltage command value for allowing an ON/OFF state of a switching element of one phase of a three-phase inverter circuit 28 to be fixed, and modulating ON/OFF states of switching elements of other two phases, and a PWM signal generation unit 36. The inter-line modulation operation unit sets a switching density of the switching element of at least one phase to a value different from that of the other phase.