Arriving at the final bid price is a critical decision which is mostly done through experience and intuitions. As, many factors affect the final proposed price, no quantified decision processes may lead to irrational low or high proposed prices. Therefore, various attempts have been done to propose systematic models to track and analyze the bidding trends. This paper focuses on the previous trends of the bidding prices to estimate proper bidding cost in the Iranian construction industry The prices might be influenced by environmental characteristics such as competitors' policies, the number of tendered projects, the number of contractors competing in the current tender, project characteristics, and the client.. The subject of bidding price can be investigated through the client view or the contractor view. This paper attends the second approach. This paper present a quantitative analysis of impact of number of bidders on project bid prices. The study found that increasing the number of bidders will result in decreased project bid prices.