Abstract: The structure of CSGR-1 (a Computer Simulator of Groundnut Rust,No. 1) is described in detail with the result of its validation test. The comparison of the results of the tests of total simulation outputs and the observed values in field with several statistical methods showed that the structure and behivor of the model is reliable. Two methods, confidence range of linear parameters and accuracy analysis,were introduced into the validation test of the model. The former resembles to a certain extent the t-test of linear parameters in a theoretical sense but the conclusion obtained is more directly percievable than that of t-test, and the latter is a mild method which only presents a parameter of accuracy, giving no definite, positive or negative, statistical conclusion.