Abstract: In order to improve the accuracy of transformer economic life assessment, a transformer economic life assessment method considering comprehensive failure rate is proposed. Firstly, based on the life cycle cost (LCC) theory, the LCC expression considering the dynamic failure rate of transformer is constructed. Secondly, the annual value data of the optimal return period and the minimum cost of the transformer under the condition of zero overhaul and random overhaul are calculated respectively. Finally, the change trend of the optimal retirement age and cost in the two cases is analyzed, and the corresponding retirement time design schemes are proposed respectively. This method can quickly obtain the annual value data such as the retirement age and the minimum cost according to the actual operation of the transformer, reduce the evaluation error of the economic life of the transformer, and support the resource saving of the power equipment.