Objective:To investigate the correlation of red blood cell distribution width-to-platelet ratio (RPR) with clinical features and prognosis of patients with multiple myeloma (MM).Methods:The clinical data of 137 patients with MM who were admitted to the Affiliated Hospital of Xuzhou Medical University from April 2013 to July 2019 were collected. The receiver operating characteristic (ROC) curve was used to determine the best cut-off value of RPR. According to the best cut-off value of RPR, the patients were divided into high RPR group and low RPR group, and the differences in clinical characteristics and prognosis between the two groups were analyzed.Results:The best cut-off value of RPR was 0.10, and according to the best cut-off value, the patients were divided into high RPR group (RPR ≥ 0.10, 52 cases) and low RPR group (RPR < 0.10, 85 cases). There were statistical differences between the high RPR group and low RPR group in the proportion of patients between different stratification of Durie-Salmon (DS) staging ( χ2 = 17.110, P < 0.01), International Staging System (ISS) staging ( χ2 = 10.817, P = 0.001), red blood cell distribution width standard deviation(RDW-SD) ( χ2 = 26.937, P < 0.01), hemoglobin ( χ2 = 17.140, P < 0.01), lactate dehydrogenase (LDH) ( χ2 = 7.926, P = 0.005), erythrocyte sedimentation rate (ESR) ( χ2 = 9.513, P = 0.002), β 2-microglobulin (β 2-MG) ( χ2 = 7.726, P = 0.005), and bone marrow plasma cell ratio (BMPC) ( χ2 = 6.621, P = 0.010). The overall response rate (ORR) in the low RPR group was higher than that in the high RPR group [82.4% (70/85) vs. 71.2% (37/52)], but the difference was not statistically significant ( χ2 = 2.366, P = 0.124). The deep remission rate in the low RPR group was higher than that in the high RPR group [56.5% (48/85) vs. 19.2% (10/52)], and the difference was statistically significant ( χ2 = 18.327, P < 0.01). The results of multivariate analysis showed that the albumin, RPR and degree of remission were independent influencing factors for the overall survival (OS) of newly treated MM patients (all P < 0.05). Conclusion:MM patients with elevated peripheral blood RPR have shorter OS time, and RPR may be one of the indicators for evaluating the prognosis of MM.