Agricultural heritage systems is a unique land use system and agricultural landscape formed under the long-term co-evolution and dynamic adaptation of the countryside and its environment, which is rich in landscape elements. The coupling of landscape elements will have impact on the supply of ecosystem services in the whole landscape. Agricultural heritage systems under human long-term cultivation has gradually formed a special landscape pattern. However, the current research on the valuation of agricultural heritage systems ecosystem services is limited to regard it as a single ecosystem, ignoring the impact of the interaction between patches on the supply of ecosystem services, such as the movement of heat, water and nutrients among patches. This research constructed a theoretical framework of "Extra services" and defined "Extra services". We took Costal Bench Terrace System in Ruian, Zhejing Province as the research object and divided its landscape elements into farmland ecosystem and aquatic ecosystem. Referring to the Millennium Ecosystem Assessment Classification System, this research used the method of ecological economics to evaluate the ecosystem services value of landscape elements, the ecosystem services value of whole landscape, and the Extra services value, respectively. The results show that:(1) the total value of ecosystem services in the Costal Bench Terrace Ecosystem was 18.772 billion yuan in 2019, and the value of cultural services was the highest, accounting for 91.8% of the total value; (2) The ecosystem service value of farmland ecosystem was 0.603 billion yuan, accounting for 3.2% of the total, while the ecosystem service value of aquatic ecosystem was 0.815 billion yuan, accounting for 4.3% of the total; (3) The Extra services value was 17.354 billion yuan, accounting for 92.5% of the total. The coupling of farmland ecosystem and aquatic ecosystem leads to the enhancement of the supply of four type of ecosystem services in raised-field agricultural system, which are food production, gas regulation, saline-alkali soil reclamation, and leisure services. This ultimately leads to the generation of Extra services.