The key technology to evaluate the durability of typical components quickly is discussed. Based on the durability condition of the whole vehicle structure of a large proving ground, the damage of the main parts of a certain vehicle model under the condition of a large proving ground is taken as the target. The characteristics of the working condition of a small special proving ground are combined to formulate the durability evaluation criterion of a small special proving ground based on the principle of damage equivalence. On the basis of a large amount of load data analysis, the target damage in the road condition of the large test field is established, and the damage is taken as the target for the small test field. The cycle number of the combined road condition is established. Genetic algorithm is used to solve the mathematical model of equivalent relationship, and the durability evaluation criterion of key parts in the small special test field that meets the needs of independent brand automobile development is reasonably designed. The method proposed by this paper can provide technical support for the efficient, accurate and low-cost evaluation of the durability of parts of different models on the same vehicle platform. It also provides a new idea and reference for the establishment of the durability criterion of the vehicle proving ground.