Abstract: Glucose oxidases (GODs) from four different sources were purified using ion exchange chromatography.The molecular weight of double subunits of GOD is about 130 kDu.Four GODs have relatively stable enzymatic properties and wide pH range after purification.Within the temperature range of 20-50℃,their enzymatic activity is relatively stable but declines with the increasing of temperature.However,enzymatic activity is less stable at 55℃ and no activity can be detected at 60℃ among GODs tested here.Metal ions including Fe²⁺,Co²⁺,Mg²⁺ and Cu²⁺ have strong inhibitory effects on these four kinds of enzymes in which Fe²⁺ is the strongest one.However,EDTA is able to activate GOD's activity.Under the condition of temperature 30℃ and pH 7.0,these four kinds of GODs are tested for K_m and K_cat values with the different concentrations (20-100 mmol/L) of glucose as sole substrate.Based on the results of UV spectra and the circular dichroism of four kinds of glucose oxidases,it shows that their secondary structures are very similar with different amino acid residues.However,GoxC,one of precursors of GOD,and some modified proteins such as precursor of catalase and putative Pc16g04630 protein can play vital roles in catalysis efficiency and their application in industry.