The invention discloses a kit for quickly detecting Seriola lalandi ascites virus and a method for detecting same, comprising a kit consisting of 6 reagents: Bst DNA polymerase, reverse transcriptase, reaction buffer solution, loop-mediated isothermal amplification mixing solution, primer mixing solution and fluorescent chromogenic reagent, and a set of detection operation program which uses the kit to detect the Seriola lalandi ascites virus in fish samples, so as to realize the standardization of quick detection on Seriola lalandi ascites virus and providing scientific basis for the healthycultivation of fish and development of international fish trade. The kit and the method have the advantages of good specificity, high sensitiveness, simple and convenient operation, high efficiency, and the like, can be widely applied to the field instant detection of aquacultural farm and import and export trade of fish, can provide technical support for relevant basic research and have wide application prospect.