Abstract: Objective To compare the effect of hand-held vibration expectoration in vitro and high-frequency vibration expectoration in treatment of severe head injury(SHI)patients with mechanical ventilation. Methods Totally 42 SHI patients with mechanical ventilation were selected and treated with auxiliary expectoration three times per day. They were randomly divided into vibration expectoration in vitro group and high-frequency vibration expectoration group. Systolic blood pressure, heart rate and expectoration volume were compared before and after expectoration between two groups. Results The vital signs in both groups were significantly improved after expectoration, and the heart rate and systolic blood pressure of the high-frequency vibration expectoration group were significantly lower than those of vibration expectoration in vitro group(P<0.05). The amount of sputum in vibration expectoration in vitro group was(5.56±2.45)mL, which was significantly lower than(6.23±3.12)mL in the high-frequency vibration expectoration group(P<0.05). Conclusion High-frequency vibration expectoration group has less influence on vital signs of SHI patients with mechanical ventilation, and its clinical application shows better expectoration effect, high operability and safety.