Abstract: During the period Ming and Qing Dynasty，the cultivating land for farming was principal saturation in the plain area. With expanding of the population the average field land of everyone was in creasing decreased, the austere survive crisis made a great deal of swarmed into the wealth resource but unexploited barred a mountainous area, sequentially people raised the wave of exploiting the mountainous areas. Economy of the mountainous areas become base of active element of society developing. This paper analyzes the population transfer and the cause of formation from the area in south of Shannxi province, during the period Ming and Qing Dynasty, and then probe into basis rule of the expanding of population and basis figure of the agriculture developing.