Objective: To optimize extraction technology of total alkaloids from Baphicacanthus cusia. Method: Based on single factor test,effects of extraction time,ethanol concentration and liquid-solid ratio on yield of total alkaloids from B. cusia was investigated with a three-factor Box-Behnken center-united design,extraction parameters were optimized by response surface methodology. Result: Optimized extraction technology conditions was as following:extraction time 20.23 min,the concentration of ethanol 83.21 %,liquid-solid ratio 21.16: 1,theoretical yield of total alkaloids could be up to 0.781%.According to actual situation in production,optimum extraction parameters were modified as extraction time of 20.5 min,the concentration of ethanol 83.0%,liquid-solid ratio 21.0: 1,validated experiment showed yield of total alkaloids was (0.78 ± 0.024)% under these conditions,which was in consistency with the theoretic value. Conclusion: This modified extraction parameters were credible and reliable with some practical value.