Objective: Study the volatile components of Tiaoyuan powder and explore its pharmacodynamic material basis for the treatments of autism and related symptoms. Method: Headspace solid phase micro-extraction (HS-SPME) and steam distillation (SD) combined with gas chromatography and mass spectrometry technique (GC-MS) were used to analyze and identify volatile components;HS-SPME-GC-MS were used to analyze volatile components before and after decoction. Result: 48 volatile components were detected by SD-GC-MS

among them 28 were identified

accounting for 85.44% of the total volatile components. 122 volatile components were detected before the decoction

73 were identified

accounting for 75.56% of the total volatile components. 50 volatile components were detected after the decoction

27 were identified

accounting for 93.49% of the total volatile components. In three experiments a total of 97 peaks were identified;the highest content was α-asarone. Conclusion: This study not only provided a methodological foundation for volatile components analysis of Tiaoyuan powder

but also provided a reference on phamacodynamic material basis for improving autism.