Abstract: In order to explore investigate the optimal conditions for the determination of biological characteristics and viability of Cinnamomum cassia seeds, morphological indexes, 1 000-seed weight, germination indexes, viability and other aspects of C. cassia seeds were studied, and the effects of different germination environment on the germination rate of C. cassia seeds were also investigated. Meanwhile, the 2,3,5-triphenyltetrazolium chloride（TTC） staining method was used to determine the viability of C. cassia seeds, and the effects of different dyeing temperature, dyeing time and TTC concentration on the viability of C. cassia seeds were further studied by orthogonal design. The results showed that the average length and average diameter of C. cassia seeds were 10.89 mm and 7.41 mm respectively, and the average of 1 000-grain weight and water content were 262.41 g and 35.99%. The highest germination rate was 76.76% under wet sand condition. In addition, range analysis showed that TTC concentration and dyeing temperature were the most important factors affecting the viability of cinnamon seeds. To sum up, wet sand could significantly improve the germination rate of C. cassia, and the best dyeing conditions of TTC method were 1% TTC concentration, dyeing for 8 h at 35 ℃.