Abstract: OBJECTIVE To optimize preparation technology of Tianyin capsules. METHODS The extraction process was studied by orthogonal experimental design as guided by the yield of extract and the content of gastrodin, total flavonoids, ginkgolides as measuring index. Granulating conditions was studied. RESULTS The optimal extraction conditions: 70 ℃, and extracted 2 times by 70% ethanol. The time for each extraction was 2 h. The first time used 12 times alcohol, while the second used 8 times alcohol. Wetting agent was 75% alcohol, extraction powder∶adjuvant was 1∶1. CONCLUSION The preparation procedure is stable and feasible, it could be used for the preparation of Tianyin capsule.