Problems such as economic losses due to fish diseases and infections, are the most important issue for the development of the fisheries sector. Current studies focus on the use of immu-nostimulants against fish diseases due to the fact that there is still no effective treatment for a few fish diaseases and the available treatments possess additional stres for fish. In this review, the advantages and disadvantages of the immunostimulants used against fish disases and stud-ies on the current immunostimulants are summarized. Climate change is one of the greatest problems the world faces today. Greenhouse gases, pesticides and heavy metals have in-creased due to the human activities and played a key role in global warming. Therefore; level, oxygen content and salinity of the water have been changed and pathogens, toxic algae in-creased at the global scale. In recent years alien species occurred and sudden massive fish kills increased in Turkish waters. Anchovy may not be seen in Turkish waters in a closed future due to the warming of Black Sea. Since seafood are sensitive to the changes in aquatic environ-ments, climate change will inevitably damage aquaculture and fishery sectors. Climate change will also threat the safety, diversity, amount, quality of seafood and seafood-borne diseases will increase. Therefore, seafood consumption will decrease and seafood processing sector will be affected negatively. To avoid these negative conditions besides decreasing greenhouse gases emissions and supporting environmental technologies; governments must create collective food safety programs. The effects of climate change on seafood consumption must be well examined and studies on this subject must be supported. The hazards, occurred as the result of climate change, must be considered in Hazard Analysis and Critical Control Points (HACCP) plans.