Since China adopted formalized and standardizedprocedures of tender and bidding in the construction industry, many illegal actions have been prevented effectively. However, the together-conspired bidding, a new illegal activity,recently emerged in many regions of China. It is widely believed that the establishedfair competition system will be frustrated and the healthy development of the industry will be harmed, if the together-conspired bidding can not be controlled. This paper firstly introduces the background of the together-conspired bidding and stressed the necessity of preventing together-conspired bidding. Then, the whole procedure of together-conspired bidding is studied and ananticipated profit model fortogether-conspired bidding is provided from the economic angle. According to the analysis on interactions between the economic factors and the anticipated profits, some strategic methods to prevent the together-conspired biddingare recommended.