The invention belongs to the technical field of power electronics, and particularly relates to an SVPWM modulation method of an H-bridge inverter. The method comprises the steps of building a Beta axis along Vab, allowing an Alpha axis to be orthogonal to the Beta axis, and dividing the whole space into a fan region I and a fan region II, wherein the fan region I is in a way that the H-bridge inverter works at [0, Phi] time frame, and the fan region II is in a way that the H-bridge inverter works at [Phi, 2Phi] time frame; obtaining modulation time Ta and Tb of each fan region from a given expected output vector voltage according to a volt-second balance principle; and inputting a triangular carrier and the modulation time Ta and Tb of each fan region, and acquiring driving signals and driving signal time frames of a switch tube S1 and a switch S3 by combining output vector voltages of the H-bridge inverter respectively used as control signals of the switch tubes. According to the SVPWM modulation method provided by the invention, the modulation time Ta and Tb is calculated again at a top point and a bottom point of each modulated triangular wave, and the problem of excessively long conduction time of a switch device of a certain phase of the H-bridge inverter to cause power and heat unbalance is solved.