A field experiment was conducted to study the effect of carbonbased organic material on contents of nitrogen and potassium content,photosynthetic characteristics,agronomic characters and yield and quality in fluecured tobacco using Qinyan 96 as materials to explore an efficient measure to ameliorate soil in tobacco field in southern Shaanxi province.The result showed that carbonbased organic material application increased contents of potassium and net photosynthetic rate,improved agronomic character and enhanced yield and quality of fluecured tobacco with application rates from 0 to 9 000 kg/hm2.The above parameters were significantly positive correlative with application amount.However,with increase application rate from 9 000~12 000 kg/hm2,the decreased effect or nonsignificant change were obtained for the above parameters.The output value and the ratio of midhigh grade leaves were negative related with application rates.9 000 kg/hm2 carbonbased organic material was the best application rate in this experiment,which could improve soil structure,enhance leaf nutrition and photosynthetic characteristics as well as yield and quality in fluecured tobacco leaves.