Abstract: The seed of flue-cured tobacco K326 was primed in 9 different treating durations, and the germinating viability, percentage and indexes of primed pelleted seed were determined.The results showed that there were significant differences of seed vigour and germinating percentage (1% and 5% levels) between all treatments and CK, and there were certain differences among different priming durations.The vigour of primed pelleted flue-cured tobacco seed was evaluated as follows:1) the germinating viability and percentage increased significantly by priming duration of 30-46h;2) the trends of germinating percentage and viability changing with different priming durations were similar;3) the higher germinating index and seed vigour could be obtained by priming duration of 35-44h.