For high-tech enterprises, building enterprise innovation ecosystem to reach collaborative innovation with others, is an important way to get access resources for research and development, and helps to maintain their competitive advantage. Based on previous studies of innovation ecosystem, this paper researches the characteristics (integrity, dynamics, complicacy and openness) and the structure especially based on innovation platform of high-tech enterprise innovation ecosystem. Then in order to explore the mechanism of high-tech enterprises innovation ecosystem, the paper focused on the four operating mechanism (symbiotic effect, competition mechanism, technology diffusion mechanism and profit distribution mechanism). It discusses the conditions of symbiosis by a simple game model, and believes that a competitive innovation ecosystem has to deal with those problems: competition, asymmetry of knowledge and technical standards, and conflict of interest. Finally taking telecommunications industry in china for example, this paper analyzes the formation, structure, operation and evolution of telecom enterprises innovation ecosystem.