Ecosystem can be understood from three levels of "structure-function-service", in which service is the subjective feeling or utility of human beings. To maintain high-quality ecosystem service, it is necessary to start from the natural attributes of ecosystem. Structure and function are the internal mechanisms for the formation and maintenance of ecosystem services, and plants are the core drivers of ecosystem structure and function. Plant functional groups are specific plant combinations and the dominant plant functional groups control the structural functions of ecosystems. The concept and classification of ecosystem services are closely related to plant functional groups. Plant functional groups are more direct bridges between ecosystem and ecosystem services. Establishing a connection between ecosystem services and plant functional groups provides a clearer direction for relevant research, and facilitates the application of research findings while deepening theoretical research. The internal relationship between the formation and maintenance mechanism of ecosystem services and plant functional groups is mainly reflected in four aspects:(1) the internal adaptability and external effects of plant functional groups are basis for the formation of ecosystem services; (2) The multifunctional characteristics of plant functional groups provide the possibility for ecosystem service collaboration; (3) Substitution and complementary effects between plant functional groups can enhance the quality and stability of ecosystem services; (4) Plant functional groups can provide nature-based solutions to ecosystem service restoration problems.