Abstract: The “middle income trap” has been a hot topic in academic circle since this concept was put forward. This paper analyzes and summarizes the related literatures of “middle income traps” from the definition of “middle income trap”, the existence debate and the driving factors of “middle income trap”. Conclusions are as follows: First, the existing literature defines the “middle income trap” in two ways: absolute income threshold definition and relative income threshold definition, and it develops from the definition of absolute income threshold to the definition of relative income threshold. Second, the results of most literature indicate the existence of the “middle income trap” and explain it with some economic theories. Third, the main factors that make the country cross the “middle income trap” are high human capital, proper export structure, perfect institutions, high openness, and reasonable income distribution. In addition, different countries have their own influencing factors when crossing the “middle income trap”. Finally, on the basis of summarizing the existing literature, this paper puts forward the deficiencies of existing research and future research prospects.

Key words: middle income trap, existence, influencing factors, survey