Ecological protection redline delineation aims to protect the natural ecological systems, which support human economic and social sustainable development, and constantly improve ecosystem services through the implementation of strict control measures. Based on the Environmental Protection Law, and related research and practices in China, we make the concept of ecological protection redlines clear, and present potential formation (including key ecological function areas redlines, ecologically sensitive or fragile areas redlines and forbidden development areas redlines). Furthermore, we confirm concrete forms of all kinds of redlines. Key ecological function area redlines are divided into land functional areas (including water source conservation areas, water and soil conservation areas, windbreak and sand-fixation areas and biodiversity maintenance areas) and ocean functional areas (including marine aquatic germplasm resources areas, important coastal wetlands, special protection islands, concentrated distribution area of rare and endangered species, important fishing waters, etc.), ecological sensitive or fragile areas redlines (divided into land ecological sensitive or fragile areas, including land desertification area, soil and water losses areas , rocky desertification areas and soil salinization areas and ocean ecological sensitive or fragile areas, including coastal natural coastline, mangrove forest, important estuarine, important sandpaper coast, sand protection waters, coral reef, sea grass beds, etc.), while forbidden development areas contain nature reserves, world cultural and natural heritage sites, landscape resorts, forest parks, geological parks, wetland parks, drinking water source areas, etc. Based on the latest national regulations for ecological protection and management of redlines, we propose ideas and measures of level delineation and classification management. According to the grading management regarding ecological function protection, this could determine specific control measures, in order to provide scientific support for strengthening ecological protection, optimizing national spatial development pattern, and promoting the construction of ecological civilization.