There is a problem of output waveform distortion caused by the dead-time effect of an inverter. Thus this paper takes a single-phase voltage bipolar SPWM inverter as the research object, and proposes a method to select the inverter switching frequency based on the minimum THD of the output voltage. First, using a double Fourier transform and Bessel function, the Fourier series expansion of the output SPWM is derived considering the dead-time effect. Through frequency spectrum analysis of the output SPWM voltage, the relationship between the THD and different switching frequencies is studied. It is found that there is an optimal switching frequency to minimize the THD of the output voltage. Secondly, the piecewise linear Lagrangian interpolation method is used to fit the formula for selecting the optimal switching frequency for different dead-times. Finally, using TMS320F28335 as the control chip, a single-phase bipolar full-bridge inverter test prototype is built, verifying the effectiveness of the theoretical analysis and the proposed method. Experimental results show that the proposed inverter switching frequency selection method reduces the output voltage THD, while reducing the switching loss and improving the DC side voltage utilization. This work is supported by the National Natural Science Foundation of China (No. 61973157).