Abstract:Informal governance can coordinate symbiotic relationships and behaviors among members, promote interdependence and interaction among members, and promote the healthy symbiotic development and value co-creation of the innovation ecosystem. Based on the social embedding theory and organizational ecology, this paper summarizes four types of informal governance: trust, reputation, cooperative culture, and joint sanctions based on existing research. Using the Logistic model, we construct a symbiosis model of the informal governance influence on the symbiosis relations evolution among members of the innovation ecosystem from the perspective of symbiosis theory, and conduct evolutionary stability analysis and simulation of the symbiosis model. The research results show that the symbiosis evolution of members of the innovation ecosystem depends on the strength of the symbiosis coefficient between members. Among them, the symbiosis coefficient of trust, reputation, and cooperative culture has a positive impact on the symbiosis evolution of system members, which is conducive to the formation of mutual symbiosis. The impact of joint sanctions on the symbiosis and evolution of system members is both positive and negative, which may produce parasitic, partial or reciprocal symbiosis. The income of the symbiosis and stable state of system members is affected by the symbiosis coefficient of informal governance and the maximum income of the main body. Informal governance affects the evolution of enterprises in the innovation ecosystem to a mutually beneficial symbiosis relationship, and provides enlightenment for the formulation of informal governance of enterprises, the realization of value co-creation and the healthy operation of cooperation and symbiosis of the innovation ecosystem.