A phasor analyzer used for judging the wiring correctness of a three-phase secondary circuit includes a parameter setting and input unit, a phase judging unit used for judging phases of three voltage circuits in the three-phase secondary circuit, a phase analysis unit used for judging wiring correctness and power consumer load characteristics of the voltage circuits and current circuits, a display unit used for displaying a phasor diagram and an analysis conclusion of the phasor analysis unit, a storage unit and an output unit outputting the analysis result. The phasor analyzer used for judging the wiring correctness of the three-phase secondary circuit performs analytical calculation on a relation between three-phase phase voltage phasors and corresponding current phasors in the three-phase secondary circuit through a software program, realizes accurate judgment of the wiring correctness and power consumer load characteristics of the voltage circuits and current circuits, can display a judgment result intuitively and clearly, avoids trouble brought by inconvenience of manual drawing of a phasor diagram or misjudgment brought by inaccuracy, and greatly simplifies an analysis and judgment process.