Abstract: The total alkaloid, nicotine, nornicotine, anabasine and anatabine in cured leaf C3F from flue-cured tobacco New K326 and Yunyan 87 growing at the altitudes ranging from 200m to 1200m in the northwest of Hunan Province were determined by capillary gas chromatography.The results showed that in both New K326 and Yunyan 87:1) the total alkaloid significantly negatively correlated with altitude (P < 0.05);2) the percentage of nicotine in total alkaloid increased with the increase of altitude (P > 0.05); 3) the percentages of nornicotine, anatabine and total micro alkaloid in total alkaloid negatively correlated with altitude;4) the percentage of anabasine in total alkaloid was scarcely affected by altitude.It was concluded that the flue-cured tobacco grown at properly higher altitude would have better smoking quality, because of higher percentage of nicotine and lower percentages of nornicotine, anatabine and total microalkaloids in total alkaloid, and the irritation of tobacco smoke would reduced.