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Chondroitinase ABC Ⅰ (ChSase ABC Ⅰ) which can degrade chondroitin sulfate(CS) and other glycosaminoglycan to oligosaccharide or unsaturated disaccharide, was fusionally expressed with maltose-binding protein (MBP) in Escherichia Coli BL21(DE3) (E.Coli BL21(DE3)) and purified for the first time in this study.The result showed that the productivity of recombinant MBP-ChSase ABC I was 3180 IU/(L fermentation liquor) with CS A as substrate, and the productivity might be the highest level when compared to the reported ones.The specific activity of recombinant MBP-ChSase ABC I was 76 IU/(mg protein) after purification.The Vmax, Km and kcatwere 18.7±0.3 μmol/L·s, 73.1±4.1 μmol/L and 586.7±10.8 s-1, respectively.Enzyme activity of the purified enzyme remained about 78% after 210 min when the enzyme incubated at 30 °C.The effect of His-tag on ChSase ABC Ⅰ was also investigated compared with ChSase ABC Ⅰ which cut His-tag for the first time.Generally, His-tag had no effect on polymeric state, optimal temperature and pH,had little negative impact on specific activity, kcat/Km and secondary-structure of ChSase ABC Ⅰ.This study might guide the application of ChSase ABC Ⅰ in industrial production.This study introduces a rapid method for highly expressing ChSase ABC Ⅰ, and might guide the process of industrial production.Furthermore, the investigation of thermostability might lead to an important guide in clinical treatment.