Ecological connectivity is a key concept in landscape and conservation biology. Increasing numbers of international studies are currently showing that coastal ecological connectivity plays an essential role in ecosystem conservation and restoration. In this study, we describe the concepts and principles of coastal ecological connectivity. Many definitions of ecological connectivity have been proposed, but no unified definition has been recognized. Based on an analysis of exiting definitions and principles, we propose that ecological connectivity is an integrated relationship (matrix) of spatial and biological interactions, in which both structural and functional connectivity should be considered. In a review of research progress, we found that the majority of coastal connectivity studies have focused on intertidal ecosystems, such as estuaries, wetlands, sea grass beds, mangroves, and coral reefs. The four major research topics in this area include: (1) exploring the relationships between ecological connectivity and population recruitment based on individual ontogenetic habitat shifts, (2) studying the role of ecological connectivity in response to climate change and population restoration, (3) quantitatively studying the correlation between ecological connectivity and population distribution and the construction of food webs, and (4) developing indicators of ecological connectivity as a tool for promoting ecosystem-based management. We also identified certain key issues for each research topic. For example, a major challenge for studies on topic (1) is determining how to quantify the correlations between connectivity and population increases. We then generalized a framework for conducting coastal ecosystem connectivity surveys and introduced a series of methods for certain key steps. These steps included defining the spatial/time scale, examining both structural and functional analyses, and investigating population distribution. Based on our review, we propose the following five key research areas for domestic studies on coastal ecological connectivity: (1) studies on biological ontogenetic habitat shifts in China's coastal areas (we provide a list of the fish species living on China's coast that switch habitats during their life cycles); (2) studies on juvenile fish distributions that exhibit spatial/temporal changes in estuarine, mangrove, and sea grass habitats, including studies on how ecological connectivity impacts population recruitment; (3) studies on the connectivity between adjacent marine protected areas based on hydrodynamic, nutrient transportation, juvenile dispersal, and adult migration patterns; (4) integrating ecological connectivity into studies on ecosystem integrity and conducting experimental studies on ecosystem resilience to climate change; and (5) integrating ecological connectivity into studies on ecosystem-based management, which is a key tool for marine protected area selection and boundary definition, as well as for decision making in the adaptive management of biodiversity conservation. In conclusion, our study describes the concepts and principles of coastal ecological connectivity, reviews its research progress, identifies existing related issues, generalizes a series of study approaches and frameworks, and finally proposes five key research areas for domestic studies on coastal ecological connectivity, which may have important implications for future studies on marine ecological connectivity in China.