The invention provides a method capable of reconstructing a three-phase current of an electromotor in full range at any time when the electromotor is driven by a space vector pulse-width modulation mode, which has simple algorithm, high university and relatively good control effects. In the method, an asymmetrical pulse-width modulation (PWM) mode is used for modulation, modulation vectors in a non-observation area are decomposed and one of the decomposed vectors has at least two different non-zero basic space vectors of which the continuous action time is longer than or equal to the action time of a minimal vector in a PWM period; and thus, the non-observation areas are avoided in a space vector PWM process , and the full-time and full-range three-phase current reconstruction and detection of the electromotor are realized, in particular vector distortion is avoided when the electromotor is controlled to be at a low speed. Moreover, the method has the advantages of greatly improving reliability, obviously reducing cost, along with simple algorithm, small code occupation and little increase of current harmonics.