The straw carbon is made by straw stalk (carbon plant corn, wheat, etc) gasified and dry distillated in 1,200°C. The experiment disscusses performance of straw carbon absorbing phenol in different conditions (time, dosage, temperature, pH value), and modified straw carbon in different conditions to improve its adsorption performance. Results show that the best conditions for straw carbon absorbing phenol is: amount ratio of phenol and straw carbon is 0.84mg/g (C phenol = 30mg/L), temperature is 35°C, pH value is 9, the best adsorption time is 5h.The optimal modified conditions is: modified with hydrogen peroxide, solid-liquid ratio is 1:1. The phenol content in simulation wastewater is only 0.47mg/L after absorbed by modified straw carbon. It is in line with GB 8978-1996 wastewater discharge standards.