Coral mucus, a rich source of organic matter, it abounds in nutrients and microorganisms, influencing carbon cycling and microbial community dynamics in coral reefs. Similar to terrestrial systems, coral mucus serves as an input carbon source, akin to root exudates, potentially causing priming effects. Such effects are well studied in terrestrial ecosystems, but their influence in marine ecosystems, especially coral reefs, remains understudied. We hypothesis that coral mucus has a stimulating effect on the microorganisms in surrounding environment, regulating carbon metabolism and ultimately maintaining the high productivity of coral reef ecosystems. In order to test it, firstly, the natural samples were collected to explore distinctions in microbial communities and their functions by metagenomic method. The results showed that the biodiversity, communities, network and functions in mucus, seawater and sediment environments were significantly different and some specific taxa and function only appeared in mucus. In order to test the mucus release effect, in the second step, indoor laboratory experiment was designed, through exposing the mucus into the environmental seawater and monitoring carbon-metabolic related contents.