Abstract: Polyporellus picipes is a white-rot fungus can degrade lignin, which is a producer of higher laccase capacity. The effects of different dilution ratio corn ethanol wastewater were studied by adding different volume of waste water into the conical flask of P. picipes in liquid culture. The process conditions of high lignin degradation rate and relative shortest degradation time were obtained by studying the regulation of wastewater time. The results showed that over 50% of chemical oxygen demand (COD_Cr) and 23.8% of lignin were removed from the wastewater. P. picipes can effectively remove the lignin of the wastewater of the different wastewater dilution rate (1%-20%), and the best removal effect of lignin was 6%, the degradation rate of lignin reached 73.5% on the 10^th day. The different wastewater-added time had a great effect on the degradation of lignin in the treatment system, the great effect of lignin degradation was obtained on the fifth day, the degradation rate of lignin is 68.4% on the 19^th day; the BOD₅/COD_Cr was improved in the system treated with P. picipes, and the BOD₅/COD_Cr values of the system were increased to 0.58 and above at the different wastewater-added time, BOD₅/COD_Cr values of the 9^th day-added wastewater system is the largest, reached to 0.64. The results may provide a reference for the practical application of the treatment of corn ethanol wastewater.