© 2020Purpose: The study aimed to evaluate the effect of progressive muscle relaxation exercises on pain in patients with sickle cell disease. Materials-Method: This randomized controlled interventional study was conducted in a hospital in Mersin, Turkey between October 2017 and July 2018. The study sample comprised 58 patients who were aged >18 years, conscious, had sickle cell disease, reported pain, and were treated with non-opioid or weak opioid analgesic based on the physician's recommendation (treatment group = 29, control group = 29). Data were collected by the individual presentation form and visual analog scale. During the study, both groups were treated with analgesics prescribed by the physician for three days. In addition to the analgesics, the treatment group was performed progressive muscle relaxation exercises for 30 minutes whereas the control group was rested. Pain level of both groups was evaluated at three time points every day for three days. In the study, frequency distributions and descriptive statistics were presented for categorical and numerical variables, respectively. Chi-square analysis, independent samples t-test, Mann–Whitney U test, three-way ANOVA, and Sidak test were used to analyze the difference between the variables. Results: The mean age of the patients was 29.59 ± 6.94 years, and 53.4% of the patients were female and 69% were single. The mean pain score of the treatment group at the third time point on days 1, 2, and 3 was significantly lower than the control group (p < .05). There was no statistically significant difference between the two groups in terms of coping methods for pain, pain location, and complaints accompanying pain (p > .05). Conclusion: Progressive muscle relaxation exercises were found to be effective in the pain management of patients with sickle cell anemia.