To investigate the effect of mindfulness on sleep quality and daytime vigilance,participants were randomly assigned to the mindfulness group and the control group.All of them were assessed with the Five Facet Mindfulness Questionnaire(FFMQ),Pittsburg Sleep Quality Index questionnaire(PSQI),and Psychomotor Vigilance Test(PVT) before and after eight weeks’ training.The results were as follows:1) After training,the FFMQ rating and daytime vigilance performance improved significantly in the mindfulness group.In addition,the subjective fatigue self-rating difference of PVT decreased significantly in the mindfulness group.However,there were no significant differences above these in the control group before and after eight weeks.2) Before training,the mindfulness group had a higher rating than the control group in the sleep disorder dimension of PSQI,while there was no significant difference after training.These findings suggested that mindfulness training could increase individuals’ mindfulness levels,promote their daytime vigilance,and improve their sleep quality effectively.