Abstract: This paper discusses the influence problem of least squares estimator for the linear regression model under the restrioted condition Using the W-K statistic under the restricted condition, we study the inflaences on the fitted values at x_i and x_j respectively while the i-th case （x'_i,y_i） is deleted. The Cook’s statistic is also used to discuss the i-th case’s influence on least squares estimator under the restricted condition.