Objective: To provide a scientific reference and method for quality evaluation according to the determination of the content of 5 standards of different specifications of cinnamon cinimaldehyde. Method: The assay was performed by HPLC on an Agilent C18column (4.6 mm×150 mm

5 μm) by DAD detector at the wavelength of 290 nm with column temperature at 30℃

the mobile phase was acetonitrile-water (35:65) with the flow rate of 1.0 mL·min-1

and the sample size was 10 μL every time. Result: Cinnamaldehyde sample volume had good linear relationships in the range of 0.009 801-0.980 1 μg with peak area

the correlation coefficient was 0.999 8 (n=6). The average recovery of cinnamaldehyde was 99.10% and the RSD was 2.20%. Conclusion: There are obvious differences in the content of cinnamaldehyde in different specifications of cinnamon and the adulterants. The content of cinnamaldehyde in Cortex Cinnamomi was the highest (42.11 mg·g-1)

and Cassia broken was the lowest relatively speaking (27.97 mg·g-1). The cinnamaldehyde content of Cinnamomum burmannⅡ was similar to Cassia broken

however

the content was only 13.44 mg·g-1 in Lindere umbellata. The present study can provide a scientific reference for clinical use of C. cassia Presl.