Objectives: In the present study, the contents of cinnamic acid and cinnamaldehyde in three different parts of Cinnamomi Ramulus (CR) (the whole body, the bark part, and the wood part) was evaluated using UPLC (ultra performance liquid chromatography) in order to investigate a suitable cutting method. Methods: Analysis was performed on SMART LC with UV detector. Reference compounds were separated on Inertsil ODS-4 column (2.1 mm × 50 mm, 3 μm, GL Science, Japan) using isolation elution with water and acetonitrile each containing acetic acid at a flow rate of 500 μL/min. Additionally, samples of CR were purchased from pharmacy of medicinal herb. Results: The correlation coefficients of the cinnamic acid and cinnamaldehyde levels showed good linearity (r2 ≥ 0.9999) over the linear ranges. Furthermore, the bark part exhibited higher concentration levels of reference compounds than the wood part in all samples. In addition the bark exfoliation rates in oblique and perpendicular-long cut samples of CR were lower than the perpendicular-short cut samples. Conclusions: These results suggested that the optimal cutting method would be able to reduce the bark exfoliation. Therefore, the oblique or perpendicular-long cutting method is considered to be a better cutting type than the perpendicular-short cutting method.