Abstract: In order to develop an optimal method of tobacco seed priming, improve the germination percentage of pilled seed, culture strong seedlings, naked seed was treated under the temperature of 20℃ in day time and 10℃ at night and combined with wetness changing, then was pilled, and the germination experiments on naked seed and pilled seed-bud were conducted in doors and in field.The results indicated that the seed vigor was effectively improved by treating the seed with changing temperature and changing wetness simultaneously.Compared with ordinary pilled seed, the germination percentage and emergence percentage of treated pilled seed-bud increased by 17.92%-18.81% and 11.56%-15.94%, respectively.The seedling emerging and forming times moved up by 3-4 days and 7-8 days, respectively.The seedlings had well-developed roots, significantly higher uniformity and percentage of strong seedling.