Fish vaccines play an important role in the control of fish diseases, especially in the control of some malignant infectious diseases, such as the prevention and cure of some viral diseases like hemorrhage disease of grass carp, spring viremia of carp, infectious pancreatic necrosis, etc., bacterial diseases like furunculosis, etc., and the control of diseases happening in large waters like lakes and reservoirs, etc. ; they are also able to avoid the inefficacy of disease treatment caused by resistance of pathogens to drugs, therefore, their use in the control of fish diseases is considered as most important means by harmless fishery. The history of fish vaccines is only a little more than 30 years in China, fortunately, they went through a rapid development period and now are at a new age during which high technologies expand rapidly, vaccines evolve sharply and traditional and new generation vaccines clash repeatedly, however, still many obstacles appeared during their development, Some of which brought more difficulties to their development, such as the variation of pathogens, diversity of antigens and limited understanding of immunity functional genes; others affected their applications, such as the ambiguity of immune response mechanism, the lack of convenient effective methods and measures in administration and immunization efficacy enhancement; still others caused no commercial fish vaccines available now in China, such as the failure in the establishment of effective evaluating systems and methods. Hence, it points out in this review that first, the development trends of vaccinology must be catered for by researchers; second, basic theories of fish vaccinology should be further perfected; then, the application and innovation offish vaccines in China should be further intensified by means of one or two grave aquatic animal diseases successfully cured; and then, the development of traditional vaccines and that of new generation vaccines should be combined; finally, in order to quicken the development of fish vaccines, new technologies should also be applied to their development of fish vaccines, depending on the research achievements of human and animal vaccinology.