The process of cortical reaction in Myxocyprinus asiaticus egg by histology,histochemistry,scanning electron microscopy,transmission electron microscopy,cell chemistry methods were observed.The results showed that the cortex of M.asiaticus could be divided into I-IV types according to its characteristics of the morphologic,contents,biochemical characteristics and ultrastructure.Cortical area cortex vesicles derived from the physiological changes of oocytes during their growth process.The cortex vesicles in the cortical reaction are in sequence released.There was extrapolation and integration in the release,and the electronic density of the containing stuff showed a weakening trend in this process.According to the release intensity of the cortex vesicles,cortical reaction could consist of the latent period,development period,climactic period,and declining period.0s after fertilization,weak cortical reaction appeared in the region which was 352.85 μm away from the micropylar apparatus,and it’s the starting point of the cortical reaction; 80s-120s after fertilization was the climax of cortex reaction;10 minutes after fertilization,the cortical reaction ended.50min-60min after fertilization,there appeared cortical vesicle in the animal pole cortex,and which occurred exocytosis,the second cortical reaction began.Cortical vesicles were speculated not only to join in the cortical reaction,but also to provide adequate membrane systems for the latter part of the plasma membrane reparation and the egg cleavage.There are some negative relationship between calcium ion and Ca2+-ATPase during the dynamic changes process of fertilization egg in M.asiaticus,and simultaneously there are two climaxes consistent with the climax of cortical reaction.Based on the result above,a calcium ion channel hypothesis was put forward.