Objective To establish a method for determining cinnamic aldehyde content in Xianggui Huazhuo capsules by gas chromatography-mass spectrometry (GC-MS). Methods The content of cinnamic aldehyde was determined by GC-MS. Separation was performed on a capillary column (30 m×0. 25 mm, 0. 25 μm) with HP-5 as the stationary phase. A programmed temperature was employed. The flow rate was 1 mL·min-1 with He as carrier gas, and split ratio was 50∶1. The injection volume was 1. 0 μL. Results The cinnamic aldehyde was well isolated from the other ingredients. A good linear relationships of cin-namic aldehyde in range of 0. 02-4. 00 mg·mL-1 was observed. The correlation coefficient was 0. 999 4. The average recovery of cinnamic aldehyde was 96. 2% , and RSD was less than 2. 11% . Conclusion The method is simple, accurate and suitable for determination of cinnamic aldehyde content.