AbstractCurrent legislation still places different degree of limitations on disposition of land contractual management right，including transfer，mortgage and inheritance，mainly due to social security function carried by rural land.On the whole，the security function of rural land in China is constantly weakening，and regional differentiation gets very distinct.Therefore，within the framework of maintaining collective ownership of rural land，systematic research on expansion and proper limitation of powers and functions of land contractual management right，from the perspective of regional difference in rural land security function，will have great practical value in providing theoretical support and scientific basis for comprehensively safeguarding farmers’（collective’s）land and property rights and interests，and advancing the construction of harmonious society.In addition，it will have enormous theoretical value in further enriching theory of property rights economics and usufruct.This study systematically arranges history of changes in China’s rural land property right and structure of right，and sums up successful experience of Civil Law System countries（France，Germany and Japan）and Anglo-American Law System countries（UK and USA）in rural land property right system and structural design of right.On the basis of existing theory of powers and functions，it presents new concept of branch of powers and functions，establishes a new theoretical framework for power and function structure of property right，and gives reasonable explanation of current collective rural land right system in China.From the comparison between income and expenditure，using 506 copies of questionnaires collected from farmers in Zhejiang，Jiangxi and Guangxi，this study performs empirical analysis on regional difference in security function of rural land.After fully understanding regional difference in security function of rural land，on the basis of respecting farmers’willingness and action response to expansion and limitation of powers and functions of rural land contractual management right，this study mainly adopts combined method of science of law and economics.From the perspective of balance between efficiency and equity，it expands powers and functions of rural land contractual management right and safeguards farmers’land rights and interests，to rebuild social structure and order.Furthermore，through appropriate policies about rural land management，it imposes proper limitations，to satisfy demands of public interest.Specifically，limitations include transfer and its limitation of rural land contractual management right，share purchase and its limitation，mortgage and its limitation，inheritance and its limitation，rural land development right and its limitation，and proper compensation for expropriation of rural land contractual management right，etc..