Cinnamon oils were isolated from the bark of Cinnamomum cassia presl by supercritical fluid extraction (SFE) and compared with steam distillation (SD). The extracts were analyzed with GC-MS. The yield from SFE was around four times as that from SD. The results from GC-MS revealed that the constituent components obtained from SFE and SD are similar while the distributions of individual compounds are different. In SFE, effects of various factors such as time (t), extraction pressure (P), extraction temperature (T), particle size (S) and flow rate of supercritical carbon dioxide (F) on the yield of target components were investigated. Favorable operation conditions were found at t = 2 h, P = 22.5 MPa, T = 50°C, S