Abstract T’ang Dynasty Chieh-tu Shih research should be based on An-Shih Rebellion that could be divided into two periods. During the former period, in response to interact with the early surrounding nations, the Tu-tu (army commander)of the residents combined with the Hsing-Chun-Tsung-Kuan to form a powerful border Chieh-tu Shih system. The latter period was a result of An-Shih Rebellion undefended, after the chaos Chang'an still as the capital, dozens of small-scale Chieh-tu Shih protective net were constructed. The former period the army power concentrated in a handful of Chieh-tu Shih gradually, forming the so-called two Western army group and three Northeast army group, the border Army commander pattern, thus An-lu-shan Rebellion occurred, T’ang Dynasty almost perished. The later period more and more small-scale Chieh-tu Shih were constructed in each Dou, so the Army power could be balanced and restrained others. There were no large-scale rebellion again , but too many Fan-chen(Chieh-tu Shih) exhausted national strength. Defiant Fan-chen selected army commander by themselves so that central government couldn’t control the Chieh-tu Shih and had no record of membership, no taxes either. Many small-scale disturbances, particularly in the area of Ho-shuo-san-chen for the most unrest. Excessive concentration of power, then occurred An-Shih Rebellion. T’ang Su-tsung had done the decision-making to decentralize and balance the army power by means of constructing more numbers of Chieh-tu Shih, each Dou had their own army power, neither was subordinate to the other. Consequently, only those who were capitulated in An-shih Rebellion could dominate the Ho-bei Duo Chieh-chen. On the contrary, Su-tsung’s strategy pushed the power of the Ho-shuo-san-chen to be formed. This article will discuss and explain how Ho-shuo-san-chen formed.