The purpose of this study is to evaluate the contribution of the ecosystem services to the agricultural sector through economic evaluation. The study based on the “market price method” and total agricultural production output estimated by using the instruction of calculating "Gross Domestic Product" issued by the National statistical office to assess the value of ecosystem provisioning services in the agricultural sector of Umnugobi aimag. As a result of the study, the contribution of the ecosystem provisioning service to the livestock sector in the Umnugobi aimag and its economic value reached 43.7 billion MNT in 2017, which is increased by 6.5 billion MNT (17.4 percent) compared to the previous year. The contribution of the ecosystem services to the crop production has increased by 30.5 million MNT from the previous year and reached at 662.5 million MNT in 2017. By defining the value of ecosystem services in key economic sectors, it is important to provide scientifically based data and information on the development of projects and plans for aimed at ecosystem conservation, rehabilitation and sustainable use of natural resources.