Abstract: To find out the effect of alkanes content on the moisture retentivity of cut tobacco,the contents of alkanes in 29 samples of cut tobacco were determined.The moisture retentivity of the samples was also evaluated,and alkanes were added back to the samples to validate their effects on the moisture retentivity of cut tobacco.The results showed that:1) The moisture loss of cut tobacco significantly negatively correlated to alkane content,i.e.,the higher the alkane content was,the less the moisture lost.The alkanes which significantly correlated with moisture loss were mainly those in the range of C₂₉H₆₀-C₃₅H_72.2) The samples added humectants containing different alkane levels in the order of equilibrium moisture content were sample added Humectant 1^#(1% solid paraffin)> sample added Humectant 2^#(0.5% solid paraffin)> sample added Humectant 3^#(0.1% solid paraffin)> control,their sequence were the same in the order of duration when the moisture content in samples reduced from 14% to 12%.Tobacco alkanes were able to improve the moisture retentivity of cut tobacco to a certain extent,the effect was more obvious at higher adding rate.