This article mainly discusses the following issues: 1) Under the inflexible socialism economic system till the end of 1970's, large amount of the surplus labor were produced in rural China. 2) After the reform and opening of the economy by the Chinese government in 1980's, the industrialization in rural China enabled nearly one hundred million rural surplus labor to be employed successfully. 3) Because of the decline in employment in non-agricultural sector in China after 1990, immigrant labor to the cities have been increased. 4) These huge immigrants from the farming area to the cities brought serious impacts to the society. In the farming area, serious shortage of backbone young population caused the "hollowing-out" of rural society and economy and declined the agricultural production as well. This problem will possibly become a large obstacle to the development of agricultural economy. 5) Thus, reconsideration should be necessary about the significance of the development of agricultural economy through promoting the rural manufacturing and service industry.