The bioactivity of Cinnamomum cassia bark extract was investigated on eggs, larvae, pupae and adults of Lasioderma serricorne. C. cassia bark extract had potent fumigant toxicity against different developing stages of L. serricorne, and the toxicity increased significantly with the increasing exposure dosage. Larvae and adults of L. serricorne were much more susceptible to the C. cassia bark extract than eggs and pupae. The corrected mortality of eggs, larvae, pupae and adults reached 33.42%, 96.21%, 31.75% and 93.68% at a dosage of 40 µL/L air after 48 h exposure, respectively. The declining order of susceptibility of different development stages of L. serricorne to C. cassia bark extract was as follows: larvae(LD50= 10.12 µL/L air), adults(LD50= 11.03 µL/L air), pupae(LD50= 56.46 µL/L air)and eggs(LD50= 92.35 µL/L air). These results indicate that C. cassia bark extract have huge potential as an alternative to synthetic pesticides for the integrated pest management of L. serricorne in future.