On basis of the features of the bill of quantities and the features of the market, as well as the the author's experience, this paper discusses on how to grasp the key points of the bill of quantities when editing the bidding document. The author holds the point that when editing the bidding document, special attention should be paid to such issues as demand analysis, contract awarding manner, types of contract price, protective contract clauses, bid evaluation method and division and description of different items of bill of quantities.