Abstract: The estimation method of variance components which are under the influence of the initial datum error is presented. Coupled equations of calculating the variance components estimation as the influence of the initial datum error is taken into consideration and the formula which is used for computing the estimate value of the standard error of unit weight are put forward. In the end, an instance is cited to illustrate that the influence of the initial datum error on the estimation of variance components should not be omitted when it is biggish.