Abstract: The present study was carried out to explain the analysis of repeated measures by using the multivariate test statistic which is suitable when the assumptions validity for univariate methods for repeated measures is dubious. Special attention was given to the test of assumptions, illustration of the multivariate analysis of repeated measures and comparative discussion with univariate methods from the point of view that the effects on the statistical inferences of lacking or making wrong statistical procedures. Results showed that how much important the necessity of validation of the assumptions for univariate statistical test for repeated measures and how much their influences on test results and interpretation are great of importance.