中文摘要：

对农业经营组织演化的经济学机理进行了系统梳理和分析。研究表明：农业生产特性使得公司化和集体化模式面临高监督和组织协调成本，中国农村土地安排的社会保障功能，使得农业家庭经营具有一定的合理性。然而，农业家庭经营本身难以克服农业资本和技术服务约束、市场准入困难和市场风险威胁，农业经营正在经历一个组织化的过程。“公司＋农户”在克服市场进入障碍和降低市场风险的同时，面临着由于合同不完全性、不公平性和机会主义导致的合约不稳定窘境；农户合作社通过农户之间的合作，能够克服农户资本和技术服务农业生产约束，通过组织化农户与企业签定合约，提升了契约稳定性，但传统的农户合作存在“搭便车”等内在缺陷，限制了服务的规模，必须进行内部制度创新，向新一代合作社演化。农业经营的外部环境和内在技术变化，必然会引起农业组织本身的变化，农业经营组织演化的经济因素和演化方向，是值得进一步关注的问题。

英文摘要：

Due to the high coordination cost of corporation and collectivization, together with a consideration of the social security function of farmland in China, small-scale household farming is reasonable to some extent. However, ultra-small-scale household farming is confronted with following constraints of the capital, technical services, market access barriers, and the risky market. Agricultural business is undergoing an organized process. The pattern of corporation plus farmer, while overcoming the market access barriers and the threats of market risks, is also in a wretched plight of instable contract caused by incompleteness, unfairness and opportunism of contracts. Farmer cooperative, through the cooperation among farmers, succeeds in getting rid of capital and technical service constraints. In addition, it improves the stability of the contract by signing contracts between farmers and enterprises. Nevertheless, traditional farmer cooperative, which possesses several internal limitations such as free-ride and thus restricts service scale, calls for innovation in its internal system and evolves into a new generation. The changes of external environment and internal technology in agricultural business are bound to result in the further evolution and development of agricultural organizations.