Abstract: In order to find out the effects of nano-carbon sol on the nutrient absorption and accumulation of flue-cured tobacco, a water-culture experiment was carried out to investigate the effects of nano-carbon sol of different concentrations on the growth, development, nutrient absorption and accumulation of cv. Honghuadajinyuan (Hongda) and cv. K326. The results showed that the nano-carbon sol of proper concentration could promote the growth and development of tobacco plant. When sol concentration was 10 mg/L, the biomass of tobacco shoot was significantly higher than that of the control. Nano-carbon sol also promoted the nitrogen, potassium, calcium and magnesium absorption and increased their contents in tobacco shoot. With the increase of nano-carbon sol concentration, the nutrient accumulations in cv. Hongda and cv. K326 varied as a parabola with the peak value at concentrations of 5-10 and 10-20 mg/L, respectively. Therefore, under water-culture condition, the appropriate nano-carbon sol concentrations for cv. Hongda and cv. K326 were 5-10 and 10-20 mg/L, respectively.