Driven by Big data, Quantum computing, Beidou application, Internet of things, artificial intelligence, virtual reality, blockchain and other technologies, digital economy in China has entered a new stage of deep participation of various economic entities, integration and agglomeration of various industries, continuous emergence of new formats and intelligent models, rapid improvement of value Cocreation efficiency, and urgent construction of new standards and systems.From the perspective of ecology, this paper creatively uses ecosystem theory, symbiosis theory and evolutionary game theory to study the composition and characteristics of digital economic ecosystem, and analyzes the operation mechanism of digital economic ecosystem.Inspired by the complex system theory, it analyzes the operation mechanism of the digital economic ecosystem.Lotkavolterra model is used to analyze the symbiotic evolution between the central enterprises and satellite digital enterprises in the ecosystem of digital economy.It focuses on the evolution goal, motivation and process of digital economy ecosystem.Finally, the main strategies to promote the coevolution of China’s digital economy ecosystem toward mutualism are proposed.