A damping evaluation method using generator oscillation energy consumption is proposed for accurately evaluate the damping of generators in multi-machine power systems. First, the expression of oscillating energy flow of the generators based on the 6th-order electric parameter model is derived. The method overcomes the conservative nature of the existing oscillation energy consumption method which is based on the 4th-order electrical parameter model. Secondly, based on oscillation energy consumption, a mode damping contribution index and two calculation methods are proposed to evaluate the generator damping characteristic in multi-machine power systems. The mode damping contribution index has clear physical meaning, and the sum of all generator indices is the attenuation factor of the oscillation mode. Finally, the accuracy and effectiveness of the proposed method are validated on the 2-area 4-machine test system. This work is supported by the Science and Technology Project of State Grid Corporation of China (No. SGZJ0000KXJS1800293 and No. 521104180019).