There are symbiotic, commersal, parasitic or epibiotic relationships between bacterial communities and marine fish and the bacterial communities are defined as marine fish symbiotic and epiphytic bacterial communities. These microbial communties inhabit the surface (skin and gill), internal tissues and organs (blood, muscle, liver, kidney), and internal spaces (gastrointestinal tract) of marine fish. Intimate relationships exist communities within and between these communities and host. The microflora play an important role in the healthy growth of host marine fish. This rapidly growing aquaculture industry, however, has experienced relatively severe disease problems owing to lack of effective control of the microbiota in rearing systems. Thus ecological and healthy aquaculture has been put on the agenda and is getting more attention, of which microbiological eco-regulation is one of the most important points. Since data on basic microbial ecology concerned at present and especially as a basic part of microbial ecology data on symbiotic and epiphytic bacterial communities, which directly relates to occurrence of diseases by microbes, of most important marine farmed fish species in China are relatively scarce, it is very necessary to study marine fish symbiotic and epiphytic bacterial communities. In the background，the aim and significance of the studies and study situation at home and abroad including the host marine fish investigated, the kinds and effecting factors of the symbiotic and epiphytic bacterial communities and the role of microflora in host were summarized and the development trend in the future was pointed out in order to provide a reference to conduct studies concerned.