Abstract: Based on the insitu observed data for dam safety monitoring at Geheyan Water Power Station on the Qinjiang River,the method of goodness of fit test for smallsamples distribution is used to compute the safety control values of monitoringparameters.From the computed results,the values of control index for dam safetymonitoring are given in the paper.These data provided a basis for safety operation of Geheyan Water Power Station.