The invention discloses a method for testing energy efficiency of an energy-saving device. The method includes the steps that based on an IPMVP, a project boundary and a project evaluation scheme are determined before an energy-saving project is implemented; an energy-saving project reference period is determined, a pre-evaluation mathematical model is established, relevant element parameters and operating data in the reference period are gathered; in the reference period, the probably-saved power energy volume is pre-evaluated after the energy-saving project is implemented, and a pre-evaluation report is formed; an energy-saving project statistical report period is determined, a post-evaluation mathematical model is established, and relevant element parameters and operating data of the statistical report period are gathered; the actually-saved power energy volume is post-evaluated after the energy-saving project is implemented, and a measurement and verification report is formed. According to the method for testing energy efficiency of the energy-saving device, the defects that in the prior art, production efficiency is low, the energy-saving effect is poor can be overcome, and the advantages of high production efficiency and the good energy-saving effect are achieved.