The 30-year term of the second round of farmland contracting has been expiring one after another. Based on the resource allocation mode with the core principle of adjusting benefits without adjusting farmland formed in the new round of 30-year pilot work of farmland contract extension in D village， J District， Y Province， this paper explores the relationship between efficiency and fairness in the pilot work of 30-year contract extension after the expiration of the second round of farmland contract. The research results show that the resource allocation mode with the core principle of adjusting benefits without adjusting farmland ， on the one hand，meets the interests of a very small number of landless rural households through the institutional heritage of large-scale social participation in poverty alleviation and rural revitalization strategy，and ensures the fairness and justice for all members of the collective economic organization at the collective level.On the other hand， the vast majority of rural households have adopted the way of extending the contract of farmland， continuously activating the free circulation of farmland management rights， promoting the efficient implementation of a new round of 30-year pilot work of farmland contract extension， and thus realizing the organic unity of efficiency and fairness. At the same time， the analytical framework for a new round of farmland contract extension pilot work for 30 years constructed in this paper further expands the application scenario of social distribution theory.