Abstract: Despite the significant achievements China has made in conserving and remedying the ecosystems, she still has to face the fact that the deteriorating trend of the overall ecological environment has not yet been fundamentally halted. Being defective in mechanism designing at the top level, fragmented in management, incomprehensive in means, weak in technical support and imperfect in support system, the existing management system fails to meet the challenge of solving the highly complicated problems in ecosystem conservation and remediation. The Third Plenary Session of the 18th Central Committee of the CPC called for establishment of a regional joint action mechanism for conservation and restoration of integrated land-sea ecosystems, which demands that with a view to integrity of the ecosystems, an appropriate eco-environment conservation and management system be established disregarding the boundaries between regions, between basins, between land and sea, between industries and between ecological elements, and integrating all the elements, functions and means, so as to implement an integrated management of the ecosystem encompassing all the elements from mountain top to sea, all the processes and all the dimensions and preserve structural and functional integrity and health of the ecosystems. Modes of and experiences in conservation and remediation of ecosystems in other countries are elaborated,status quo of and problems in conservation and remediation of ecosystems in China are analyzed, and in the end some advice and suggestions for establishment of the regional joint action mechanism for conservation and remediation of the integrated land-sea ecosystems are put forth.