In bid evaluation, the regular grade method on the grade items is that the grade message is composed of average value after throwing away the highest and lowest value, which essence is considered that the expert’s weight is zeroed. It is pointed the processing is too simple and unable to deal with all kinds of problems effectively in the match. Basing on numerical statistics, referencing multiple attributes and comprehensive decision theory, a grade method is put forward to empower expert weight. The method according to the results consistence of the expert grade determines the grade weight, then correcting their grade weight to each specific bid, fully using all grade message coming from the bid evaluation team. Its computation is simple and easy to computer processing. So it has larger practical value. Last, the new method is used in bid evaluation on excavation support project located in Wenchang Garden, Yantai Development Zone. It shows the practical value of this method.