Objective: We study on the transmigration ingredient in cerebrospinal fluid with SiNiSan Freeze-dry Powder in order to provide dependable evidence about determining that Sini San can enhance the sleep function with drug effect material base. Method: We use HPLC method, the gradient elution, and determine the transmigration ingredient of cerebrospinal fluid in Sini San Freeze-dry Powder. The chromatograph condition: Hypersil C18 column (4.6×250mm, 5µm), speed of flow 1.0 ml/min, column warm 28, flowing A is acetonitrile; Flowing B is 0.05% phosphorus acid water, the analysis time is 140 min. Results: By the analysis of the peak area in cerebrospinal fluid, we found that the endogenous substance in cerebrospinal fluid was increased obviously with Sini San Freeze-dry Powder. From Increasing peak area of the endogenous substance in cerebrospinal fluid, mixing standard preparation's (Paeoniflorin Naringin Saikosaponin C Glycyrrhetinic acid) is 3.2 times Sini San's. Conclusion: The specificity and characteristic of the cerebrospinal fluid HPLC fingerprint mark in Sini San are strong, which can use to the transmigration ingredient of cerebrospinal fluid in Sini San Freeze-dry Powder.