The characteristics of total vector error(TVE) are analyzed by proceeding from its basic concept. The commonly used amplitude error index and phase error index are compared with the TVE index. The comparison results show that there exists a very intimate relationship between the TVE and the amplitude-phase errors, and the two of them each have their advantages and disadvantages in the static accuracy evaluation of the phasor measurement unit(PMU). So, it is recommended that appropriate evaluation indices be chosen according to the test results and the key contents in the test. The key points of PMU TVE testing are proposed.