Abstract: The seed viability was determined by TTC method, and the effects of dyeing time, TTC concentration and dyeing temperature on TTC dyeing were investigated by single factor test and Box-Benhnken response surface test. The results showed that the optimal conditions for TTC dyeing of pueraria seeds were as follows: dyeing time for 2 hours, TTC concentration of 0.57%, dyeing temperature at 37.3 ℃, the average viability of pueraria seeds was measured to be 84.44% under the optimized conditions. The error of the predicted value was 3.71%（＜5%）, indicating that the response surface methodology was feasible to optimize the TTC determination conditions of pueraria seeds.