The population quantity change of West Han dynasty generally may be divided into three periods: From the early period of West Han to the early period of Emperor Wu (202-130 BC) was the period while the population was rapidly increasing; from the middle and later period of Emperor Wu (129-87 BC) was the stagnating even decreasing period because of the abnormal death of large amount of people owing to civil war and so on. Then the population decreased to about 28 million. From Emperor Zhao to the second year of Yuanshi of Emperor Ping (86 BC-2) while the social order got quite stable, the population increased to the peak period while the population increased to over 59 million. But this number in fact was not the real one of the late period of West Han dynasty. It is only counted according to the record of'residence booklet "made by various states. The real one should be that including the hidden population, royal population, various marquises, the population of the Western regions and the minority nationalities there governed by central government. In fact the total population of the late period of West Han dynasty could reach 64 million.