Abstract: Accounting for the value of farmland ecosystem services serves as the theoretical basis for formulating policies on agricultural ecological protection compensation and ecological damage compensation and is the foundation for promoting the realization of the value of agricultural ecological products. From the interdisciplinary perspective of ecology and economics, this study attempted to integrate ecological accounting with economic accounting, thereby constructing a method to account for the value of farmland ecosystem services. Moreover, we studied the changing characteristics of the value of farmland ecosystem services in the Inner Mongolia Autonomous Region from 2000 to 2022. The results are as follows: 1) From 2000 to 2022, the average annual value of farmland ecosystem services in Inner Mongolia Autonomous Region was 5.21×10¹¹ ¥, equivalent to 79.70% of the average annual regional GDP and 11.02 times the average annual value of provision services. 2) Among the primary indicators, the value of reconciliation services accounted for the largest proportion (38.32 %) of the total value. Social security services ranked second (35.92%). Cultural services, provision services, and negative value accounted for 16.52%, 9.04%, and 0.19%, respectively. 3) Calculating the agricultural subsidy standard based on the amount that farmers should have received, however, did not receive from the total value of farmland ecosystem services, the subsidy standard per hectare of farmland in Inner Mongolia should be 51 293 ¥, which is notably higher than the current government subsidy standard of 2 250 ¥·hm⁻². The conclusions of this study imply the following policy implications: First, it is necessary to continuously explore more scientific methods for evaluating the value of farmland ecosystem services to understand the inventory and value of the farmland ecosystem. Second, it is essential to establish and improve farmland ecological protection mechanisms based on value accounting and to scientifically formulate agricultural subsidy standards. In Inner Mongolia, agricultural subsidy standards should be raised. Third, based on the ecological service values of different crops, the subsidy standards for different crops should be explored such that farmers can receive fairer and more reasonable compensation or subsidies when facing land expropriation or engaging in agricultural planting.