The realizations of digital energy measurement and traditional energy measurement bear significant differences. The organic combination of the algorithms in the merging unit and digital input electricity meter together forms the digital energy measurement algorithm, and the measured object is subject to the IEC61850 communication protocol. On this basis, different categories of algorithms applied to the system are reviewed and compared, including the interpolation algorithms such as Lagrange algorithm, Aitken algorithm, etc., the full-wave energy algorithms such as point-summation algorithm, Newton-Cotes algorithm, etc., and the electrical parameter analysis algorithms such as quasi-synchronous algorithm and windowed interpolation DFT. Meanwhile, the latest progress made in the digital energy measurement algorithms is explored, and the necessity, feasibility and direction of studying the special algorithms for digital energy measurement system are discussed.