Bacillus subtilis cotA gene which was designed According to GenBank. cotA gene was transformed to Escherichia coli BL21(DE3). The recombined CotA protein was expressed by IPTG induced method. The CotA protein was stained red by syringaldazine after Native-PAGE.The effects of the condition of induction expression on enzyme production of recombinant Escherichia coli were investigated. The result showed that the highest enzyme activity of recombinant CotA could be achieved under the following conditions: the concentration of IPTG was 1.0 mmol L-1, IPTG was added to the culture given a final concentration of 1.0 mol L-1 when the OD600 of culture reached 1.0, induction time was 12 h at 25°C. The CotA laccases could decolorize Remazol brilliant blue R (RBBR) and Congo red with 87% and Isatin and Crystal Violet with 55%. The result indicated that the CotA laccase had the potential to be industrial enzyme.