The biochemical characteristics of isoenzymes of the amylase in three major parts i.e. embryo, endosperm and radicle of wheat seeds of during germination were investigated by the native PAGE. The results showed that the optimum pH value was approximately 5.2 and the enzymatic activity was relatively stable during pH 5.0~9.0. The optimum temperature was 40℃ while most of the amylase isoenzymes kept their activities during 0℃~50℃. Heavy metal Hg²⁺s howed the most serious inhibition on the activities of isoenzymes of amylase and their activities were almost totally inhibited. Other metal ions such as Cu²⁺, Pb²⁺, Zn²⁺, and Ca²⁺ also showed inhibition on the activities of isoenzymes of amylase to different extent.