Abstract: By use of 12L glass fermentor, the bacteria count, the concentration of total sugar, reducing sugar, amino nitrogen, dissolved phosphorus, dissolved oxygen, ammonium ions, nucleic acids, ATP, pH extracellulor proteinase and viscosity in the fermentation broth of different growth periods are determined. The metabolic chart of growth process of B.t shows the relationship of different parameters, which has certain guiding significance for controlling the B.t fermentation process and increasing the fermentation level.