Objective: To choose optimal flow phase parameters and establish a content determining of ginsenoside Rg_1,Rb and notoginsenoside R_1 in Huang Qi Capsules by HPLC. Methods: The octadecyl silane chemically bonded silica was used as filler,acetonitrile as mobile phase A and water as mobile phase B. Results: The optimum gradient: 0 ~ 30 min,acetonitrile: 19 →40,and water: 81 →60. On this condition,the sample size of ginsenoside Rg_1: 0. 8496 ~ 7. 6464 μg,Rb_1: 0. 8538 ~ 8. 8538 μg,and notoginsenoside R_1: 0. 2...