Abstract: Under the traditional pulse width modulation (PWM)+sinusoidal pulse width modulation (SPWM) hybrid modulation scheme, the DCM single-leg-integrated Boost inverter will confront over-modulation problem when the load changes in wide range, leading to the distorted output waveform. By keeping the boost-leg duty cycle constant and regulating load power can address this issue. However, it is not suitable for standalone inverters and photovoltaic grid-connected systems. Therefore, a pulse-frequency- modulation (PFM)+SPWM hybrid modulation scheme is proposed in this paper. Under the proposed scheme, the boost-leg of the inverter works in PFM while the other leg works in SPWM. Since the dc-link voltage is controlled by frequency, instead of output power or duty cycle, the inverter can also avoid over-modulation for wide load range. Besides, the proposed scheme can be applied in occasions where the load power is non-adjustable, which is more practical in comparison with the traditional one. The feasibility of the proposed hybrid modulation is verified by simulation and experiment through a 500W prototype.