OBJECTIVE： To investigate the effects of different dose compatibility of Scutellaria baicalensis-Rheum palmatum- Coptis chinensis based on Sanhuang Xiexin decoction （shorted for Xiexin decoction） on dissolution rate of baicalin and baicalein， and to provide reference for studying chemical mechanism of TCM compound dose composition compatibility. METHODS： HPLC method was used to determine the contents of baicalin and baicalein. By fixing the dose of S. baicalensis （3 g）， using the dose of R. palmatum and C. chinensis as factors， dissolution rate of baicalin and baicalein as response value， two-factor and five-level central composite test was designed. The optimal dose compatibility of S. baicalensis-R. Palmatum-C. chinensis was optimized by response surface method， and compared with the dissolution rate of baicalin and baicalein in classic dose Xiexin decoction （S. baicalensis 3 g， R. Palmatum 6 g， C. chinensis 3 g）. RESULTS： When the doses of S. baicalensis， R. palmatum， C. chinensis were 3， 1.76， 0.17 g， total dissolution rate of baicalin and baicalein was the highest in extract. The average total dissolution rate of baicalin and baicalein in validation test was 21.89％ （RSD＝0.46％， n＝3）， and the relative error was 2.88％ with the predicted value of 22.54％. Compared with the classical dose of Xiexin decoction， the total dissolution rate of baicalin and baicalein in the optimum dose of S. baicalensis-R. Palmatum-C. chinensis in extract was increased by 47.21％. CONCLUSIONS： The different dose compatibility of S. baicalensis-R. Palmatum-C. chinensis based on Xiexin decoction influence the dissolution of baicalin and baicalein to certain extent. When the doses of S. baicalensis， R. palmatum， C. chinensis are 3， 1.76， 0.17 g， dissolution rate of baicalin and baicalein are higher than that of classic dose.