To solve the issue of verification and traceability of a digital energy meter, this paper presents a point of view that the traceability of the digital energy meter only involves numerical traceability and no dimension is passed. Further the theoretical basis of the view is argued. Then the paper analyzed the problems existing in the practical application of traditional standard source method. Finally, a new standard digital power source method is proposed, which can effectively solve the problem of verification and traceability of the digital energy meter. This paper also specifies the set of random functions and harmonics, the numerical accuracy of the new digital power source, and the verification procedure in different cases.