Objective: Research of the compatibility of Corydalis Rhizoma with Carthamus Flos on the dynamic change of tetrahydropalmatine for regulation of Chinese crude drug compatibility and discussing the rationality. Method: The compatibility of Corydalis Rhizoma with Carthamus Flos after the decoction of two kinds of effective ingredients was studied to determine the dynamic change of tetrahydropalmatine. Result: The tetrahydropalmatine content decreased at 75 minutes after compatibility of Corydalis Rhizoma with Carthamus Flos. Conclusion: Compatibility of fumaric with Carthamus Flos can reduce tetrahydropalmatine content, and the results can provide theory basis for compatibility test.