AIMS AND OBJECTIVES: Although many studies have assessed the efficacy of yoga in older individuals, minimal research has focused on how nurses use yoga to improve sleep quality and to reduce work stress after work hours. We used the Pittsburgh Sleep Quality Index in Chinese and the Questionnaire on Medical Worker's Stress in Chinese to determine the impact of yoga on the quality of sleep and work stress of staff nurses employed by a general hospital in China. BACKGROUND: Disturbances in the circadian rhythm interrupt an individual's pattern of sleep. STUDY DESIGN: Convenient sampling method. METHODS: One hundred and twenty nurses were randomised into two groups: a yoga group and a non-yoga group. The yoga group performed yoga more than two times every week for 50-60 minutes each time after work hours. The NG group did not participate in yoga. After six months, self-reported sleep quality and work stress were compared between the two groups, and then we used linear regression to confirm the independent factors related to sleep quality. RESULTS: Nurses in the yoga group had better sleep quality and lower work stress compared with nurses in the non-yoga group. The linear regression model indicated that nursing experience, age and yoga intervention were significantly related to sleep quality. CONCLUSION: Regular yoga can improve sleep quality and reduce work stress in staff nurses. RELEVANCE TO CLINICAL PRACTICE: This study provides evidence that hospital management should pay attention to nurse sleep quality and work stress, thereby taking corresponding measures to reduce work pressure and improve health outcomes.