Promoting ecological protection on the basis of collaboration，participation，and common Interests of the Pearl River-Xijiang River Economic Belt is a key access to strengthening the ecological construction and environmental protection in the basin areas of Pearl River and Xijiang River as well as an important measure to realize the cross-regional cooperative and coordinative development of the two rivers. At present，ecological civilization construction is at a cocrucial period of dealing simultaneously with the slowdown in economic growth，making difficult structural adjustments，and absorbing the effects of the previous economic stimulus polices. Certain achievements have been made in constructing and protecting the ecological environment in the Pearl River-Xijiang River Economic Belt，but problems still exist such as heavy task to protect the environment，difficulties in promoting transregional coordination，incomplete system for regional ecological synergies，thus solving the problems in environment treatment in the belt es extremely urgent. On the basis of the analysis of ecological conservation and protection of the Pearl River-Xijaing River Economic Belt，this paper further discusses the approaches to realize ecological protection on the basis of collaboration，participation，and common Interests of the Pearl River-Xijiang River Economic Belt，namely，building a long-term mechanism and improving the legal guarantee for the ecological co-construction，co-management and sharing of the belt，actively guiding the various entities to participate in the environmental protection and ecological management，and continuing to build the Pearl River-Xijiang River Green Corridor which helps realize the dividends from green development.