Abstract： Objective:To observe the clinical efficacy of the acupressure wrist strap in the prevention and treatment of motion sickness during navigation.Methods:A total of 178 naval recruits with a history of motion sickness were selected by questionnaire survey，who then were randomly divided into observation group（the acupressure wrist strap group）with 89 cases（2 cases dropped out）and control group（the sham acupressure wrist strap group）with 89 cases（5 cases dropped out）. The Zone Upper 2 on both sides of the wrist，which were just at the position of Neiguan point，were chosen as acupressure points. The Graybiel’s motion sickness scores and motion sickness severity grades at 2 h and 1 d after the onset of motion sickness，and the changes of heart rate and blood pressure before and after motion sickness were observed in the two groups.Results:There was a significant difference in the Graybiel’s motion sickness scores between the two groups at 2 h（the score of the observation group was 10.63±9.56，and that of the control group was 14.08±9.19， t=-2.405， P=0.017）and 1 d（the score of the observation group was 6.61±4.49，and that of the control group was 8.45±5.13， t=-2.503， P=0.013）after the onset of motion sickness，and the Graybiel’s motion sickness score of the observation group was lower than that of the control group. There was a significant difference in the motion sickness severity grades between the two groups at 2 h and 1 d after the onset of motion sickness（ P<0.05）. There was a significant difference in heart rates between the two groups after the onset of motion sickness（ P<0.05）. The heart rate of the observation group was lower than that of the control group. There was no significant difference in blood pressures between the two groups after the onset of motion sickness（ P>0.05）. Conclusion:The acupressure wrist strap has a certain degree of effect in preventing and treating motion sickness by effectively reducing the symptoms and stabilizing heart rate with the advantages of low cost，simplicity，few side effects，which is worth of clinical application.