摘要:Background and Aim: The postpartum period is a critical then effects on the structure of the family. Most women in the postpartum period may place at risk of undesirable experiences such as changes in sleep patterns. Therefore, this study aimed to identify the efficacy of the relaxation program on sleep quality of mothers with premature infants. Materials and Methods: This study is a clinical trial that 60 mothers with premature infants. The mothers in the intervention group were trained for muscle progressive relaxation by Jacobson method within 24–72 h after delivery. Research tool was the Pittsburgh Sleep Quality Index, which was completed by the mother at the beginning of the study, end of the first and the second 4-week. Data were analyzed using parametric statistics tests by SPSS software version 16. Results: No significant difference was observed between two groups in terms of underlying characteristics ( P 0.001), mean sleep quality score in the intervention group was significantly less than the control group. Conclusion: Relaxation training can improve mothers' sleep quality at postpartum period.