Abstract: In order to further broaden the application of Cinnamomum cassia leaves essential oil in food, feed and other fields, C. cassia leaves essential oil/β-cyclodextrin microcapsules were prepared by co-precipitation method with β-cyclodextrin as the wall material and C. cassia essential oil as the core material. The preparation conditions of microcapsules were optimized by orthogonal experimental design. Essential oil/β-cyclodextrin microcapsules were characterized by using gas chromatography-mass spectrometry(GC-MS) and Fourier transform infrared spectroscopy(FT-IR).The results showed that the suitable preparation conditions of microcapsules were wall-core ratio 6:1, temperature 50℃, time 4 h and stirring speed 1 000 r/min. The encapsulation efficiency of C. cassia essential oil of the obtained microcapsule was 74.17%. The GC-MS analysis showed that the main compositions of C. cassia essential oil were trans-cinnamaldehyde(81.39%), followed by o-methoxycinnamaldehyde(7.61%) and the main compositions of C. cassia essential oil in the microcapsule were also trans-cinnamaldehyde(78.68%) and o-methoxycinnamaldehyde(9.34%). FT-IR analysis showed that C. cassia leaves essential oil and β-cyclodextrin formed good inclusion complex. C. cassia leaves essential oil/β-cyclodextrin microcapsules had good thermal stability and slow-release properties.