Abstract: At present, the underwriting fee is too low in the bond market of our country. The pricing standard of underwriting fee deviates from the market law, this kind of non-market pricing behavior will disturb the order of the market, hinder the fair competition and bring risks to the development of the market. In this paper, the underwriting fee is too low non-market pricing to carry out in-depth analysis. Specifically, the formation mechanism of the phenomenon of low underwriting fee can be analyzed from four aspects:regulatory system, legal policy, profit model and competition. At the same time, the phenomenon of low underwriting fee may lead to market risks from these four aspects at the same time, phenomenon and formation mechanism are cause and effect each other. Therefore, effective risk control has important practical significance.