Based on the literature review about the changing history of agricultural science and technology policies in China,this paper analyzes the complex system of the special policy structure along with different administrative and professional levels driven by the power of administrating intervention and market force.A new way to divide this special policy structure is according to public and non-public categories.This paper concludes that although agricultural science and technology have some points for pro-smallholders,it is not smallholder-centered.So,it is recommended that smallholder-centered could be a key principle to be used for improving the agricultural science and technology policy system in China.