Abstract: Blocking high is a phenomena of persistentanomaly of at mospheric circulation,weather and climate anomaly could be aroused in the close areas under the background.Many kinds of definition of blocking high are given in the past studies,mainly in two categcries:the first definitions base on the climatic characteristics,attention were pald to the anomaly of geopotential height field;the second base on the synoptic features,such as center of high appear or not,how long the high persist,etc.Appropriate definitions could be selected according to the purpose ofresearch and the place of your study.Blocking high is stability nonlinear system of forced dissipation,most of researches applied to the multi-equilibrium states theory,the forced resonance theory,the nonlinear solitary Ross by waves theory,the baroclinic property theory and the wave-flow interaction theory to explain the formation of blocking high,mostimportant results were obtained.The farther studies about mechanism of blocking high would be continued.