Abstract: Using tissue culture technique,embryonic callus derived from tobacco (NC-82) leaf were transferred to Murashige and Skoog(MS) media supplemented with median lethal concentration of tribenuron-methyl and selected for 3 generations. The resistant calli were cultured on hormone-free media supplymented with tribenuron-methyl and regenerants were induced.The tobacco regenerants that resistant to tribenuron-methyl were screened,the regenerant seeds vigor and resistance ratio were determined.It was found that the regenerant seeds vigor index and that of the control were 10.81 and 9.53,respectively,the peroxidase activity were 47.36 and 29.44 U·g-1·min-1,while acid phosphatase activity were 2.927 and 2.447 nmol·g-1·min-1 ,respectively.The identification of resistance potential indicated that the herbicide resistance of regenerant seeds increased,the resistance ratios was 3.18.The ALS activity of the regenerant seedlings and that of the control were 10.41 and 6.67 nmol·h-1·mg-1,respectively.