Based on the Input-Process-Output approach (IPO) developed by David S. Bushnell, we construct a model for training evaluation. In this model, we discuss the relationship between training input and training process, and their impacts on training effectiveness. Moreover, we take training process as a mediator variables and examine the moderating effect between training input and training effectiveness. As a result, we find that: (1) there is a positive correlation and influence between training input and training process; (2) there is a positive correlation and influence between training, input and training effectiveness; (3) there is a positive correlation and influence between the training process and training effectiveness; (4) training input influence on training effectiveness as training process served as a mediator.