This paper is the result of environmental geolgical survey engineering. [Objective] In order to support and provide a scientific plan for coastal ecological protection and restoration, it is necessary to figure out the laws and trend of natural coastal evolution processes. [Methods] Based on systematic collection and summarization of achievements on the evolution of the mainland coasts of China, combined with drilling cores comprehensive research, remote sensing interpreting and ArcGIS spatial analysis, the coastal history since the Last Glacial Maximum (LGM) was quantitatively reconstructed. [Results] The results showed that seawater frequently entered and exited the coastal areas since 2 million years ago. The last large- scale transgression- regression occurred in the past 20 ka, which can be divided into three phases: the coasts experienced the LGM-early mid-Holocene transgression, the Early mid-Holocene-1850 CE regression, and a new transgression again since ca. 1850 CE. [Conclusions] According to the analyzed results of the existing instrumental data, the coasts of the Chinese mainland and the world will face accelerating sea-level rise, increasing coastal erosion, and increasing storm surge threats in the future, which will be a key issue of ecological protection and restoration. In view of this, the following suggestions are put forward for the ecological protection and restoration of the coastal zone: First, for sandy coasts, while following the overall natural erosion background, the appropriate restoration strategies should be applied to the shore section with important ecological and economic values, and to avoid large-scale over-repair; The second is to determine scientifically feasible restoration targets in view of the squeezing of the mangrove ecological space caused by sea level rise and coastal erosion; The third is to strengthen the construction of ecological seawalls in the muddy coastal lowland areas.