Statistics of red tides and its real time information promulgated by the relevant national office bring difficulties into red tides studies and cognition by the public due to lacking the maneuverable uniform information standard. Generally, the public pay more attention to the characteristics of red tides impacts, and its sizes, when HABs outbreaks. In order to facilitate the data statistics and management of HABs disaster as well as uniform its information publication, present paper combined historical data and state-of-arts HABs status in Chinese coast so as to build up a system for early warning of HABs and its hazard classification and grading according to the characteristics of HABs. The results of this study revealed that HABs in China can be divided into four types based on the characteristics of HABs causative species and the effects of HABs on the human health and mariculture. They are: toxic species, fish-killed species, harmful species and unharmful species. Toxic species which causes human illness includes Alexandrium catenella, A. tamarense, A. minutum, Gymnodinium catenatum, Dinophysis acuta, D. acuminate, D. rotundata, Prorocentrum lima, Karenia brevis, Pseudo-nitzsdia multiseries, P. pseudodelicatissima, Gambierdiscus toxicus, etc. Fish-killed species which has implication to mass mortality of marine fish-caged organisms contains Karenia mikimotoi, Phaeocystis globosa, Chattonella marina, etc. Harmful species includes Chaetoceros spp, Noctiluca scientillans, etc. Some of these organisms are not toxic but cause marine products die because of suffocation. Unharmful species which is non-toxic includes Skeletonema costatum, Coscinodiscus spp., Mesodinium rubrum, etc. In addition, accounting for the large differences in sizes and their duration, HABs can be divided into three grades of large, middle and small. Their sizes are: larger than 1000km2, between 1000km2 to 100km2, and smaller than 100km2, respectively. Thus, HABs occurred in Chinese coast can be clarified as 12 degrees and indicated by different colors and signs in order to facilitate publication by media. Further, the aims to mitigate HABs disaster and protect human health can be achieved by establishing the early warning system and lash-up management measure for these different kinds of HABs.