It is necessary for the intelligent Decision Support System(DSS) to automatic select models, but there is less the available arithmetic. The paper provides a method that solved the automatic model selection problem by intelligent Agent. The method uses BDI Agent’s belief to describe the question, and uses the rulers of belief to desire to select the model type. Then the model selected Agent communicates with the model-Agent by the contract net protocol to select the model structure. The experiment result shows that the method can solve the automatic model selection preferably.