Abstract: By making use of the data from the Chinese General Social Survey (CGSS) 2015, this paper establishes a multiple mediation model to analyze the affecting mechanism of the children education level of low income families on the chances of upward mobility of the class and compares the changes of the various affecting mechanisms at the different periods. The results show that: (1) in China, education investment is the major path to increase the upward mobility opportunities for low-income families, and the higher the education level, the more opportunities for class upward; (2) the improvement of education level will change individual’s knowledge skill and learning ability, thus further influence the opportunity of class mobility, this path makes the biggest contribution to the obstructing of the intergenerational transmission of poverty, which will be strengthened along with the passing of the time; (3) the contribution made by education through affecting job motivation is limited, which can only affect class upward movement of those with higher education experiences.

Key words: educational investment; opportunities of class upward mobility; multiple mediation model