在工程项目招投标时，标底在评标过程中对工程造价和承包者的利益有直接影响。目前，编制用于招标的标底大多是与招标书同时完成，即在开标前早已确定并用于评标。多种确定标底的方法有着各自的优缺点。我们在实践中，于开标以后评标之前，既计入编标时的标底，又照顾众多投标者的报价，采用系数法的计算公式求得评标用的综合标底。这样确定标底对保密有利，而且比较客观。 Bidding in the project, the tender in the bidding process on the project cost and the interests of the contractors have a direct impact. At present, most of the bids compiled for bidding are completed at the same time as the bidding documents, that is, they have already been identified and used for bid evaluation before the bid opening. A variety of methods to determine the bottom have their own advantages and disadvantages. In practice, before bid opening after the bid evaluation, both included in the tender at the end of the tender, but also take care of the bidder's bidding, the use of the coefficient method of calculating the standard bidding for evaluation. This determination of the bottom of the confidentiality of good, but more objective.