The state of carbon in biochar is important in mutual actions between biochar and soil in light of carbon sequestration and soil amelioration, and is affected by pyrolysis temperature.In the present study, peanut hull biochar were made at 300℃, 500℃ and 700℃ separately and used to analyze the content of total carbon and fixed carbon.Carbon distribution in organic matter of biochar was also surveyed.The result showed that, when total carbon content increased from 70.55% to 85.96%, the fixed carbon content also increased from 41.22% to 53.63% with increasing pyrolysis temperature.If the fixed carbon was taken out of consideration, the revised C/N ratio was dramatically reduced, ranging from 21.80 to 32.01 compared with the original C/N of 59.79 to 85.11.Carbon distributed in each component of organic mater of biochar, and their contents increased with the rise of highest treatment temperature.The result of mass spectrum analysis showed that the types of carbon containing compounds in biochar decreased from 119 at 300℃ to 21 at 700℃.All the results indicated that carbon in biochar was both reactive and inert, and might be suitable for carbon sequestration and soil amelioration at same time.