This test used tobacco as raw materials,methanol as impregnant,extracted nicotine in tobacco by ultrasonic wave,and studied relationship of different concentrations of methanol (x1),ultrasonic time (x2),the ratios of material to liquor (x3) and the quantity of nicotine (y) by using method of multiple regression orthogonal design.Then determined nicotine by gas chromatography.The results show that the appropriate conditions of ultrasonic extraction of nicotine in tobacco:the concentration of methanol was 40%,ultrasonic time was 45 min,the ratio of material to liquor was 1 ∶ 20.