In order to separate the impacts of the climate change and human activities,it needs to separate the impacts of the multi-factors. When using the traditional methods to calculate the contribution of multi-factors,the sum of each factor′s contribution is not always equal to the comprehensive changes because of the interrelation between each factor. Thus,most of the traditional methods focus on the two factors contribution analyses. A new method,which is based on the simulation of the distributed hydrological model,is promoted to solve this problem. The new method could handle the interrelation between different factors, and assure that the sum of each factor′ s contribution just equals to the total changes, which is proved theoretically and practically in this paper. Contrasting to the traditional methods, the new method could partition the contribution of more than two factors,and it is flexible to select the base period and impacted period. Moreover, the new method could be used in study of atmosphere, environment, ecology,and so on,as well as water cycle,combining with the physically based simulation models.