Objective: To investigate effects of different pretreatment methods on vacuum reflux extraction efficiency of Epimedium brevicornum. Method: Taking yield of icariin as index

vacuum reflux extraction technology of E. brevicornum was optimized by orthogonal test with vacuum degree

extraction time

temperature and times as factors

single factor tests were adopted to investigate effects of soaking time and crushing degree on vacuum extraction efficiency of E. brevicornum. Result: Optimum vacuum extraction technology was as following:extracted 3 times with 10 times the amount of 60% ethanol

20 min each time

vacuum degree 0.07 MPa.Yield of icariin increased by 9.5% after E. brevicornum crushed into fine powder

it was 7.9% after crushed into coarse powder

and extract yield increased by 2.6%

1.7%

respectively.After soaked different time

yield of icariin increased by 6.4% and dry extract yield increased by 6.9% at most

soaked 20 min had optimal extraction efficiency

but coarse powder and fine powder had no significant differences. Conclusion: Yield of active ingredients and dry extract rate of E. brevicornum would increase under different pretreatment methods.