Patients with pulmonary embolism (PE) have a higher red cell distribution width (RDW), which may complicate the interpretation of the prognosis of PE. We aim to evaluate the diagnostic utility of the RDW in patients with PE. Eligible studies were identified by searching PubMed and EMBASE from inception to December 23, 2018. The data were pooled using Stata 12 to evaluate the prognostic value. The sources of heterogeneity were detected. For the analysis of prognosis, 7 studies with 2146 patients were included, with median RDW values ranging from 13.4% to 15.7% and a median cut-off point of 18.27%. A total of 247 patients (11.5% mortality) among the 2146 participants died. Overall, RDW was positively associated with the prognosis of PE in the overall analysis (HR = 1.19, 95% CI = 1.10-1.29, I2  = 73.4%; P = 0.000). Subgroup analyses by study design, sex and follow-up time indicated that they were not sources of heterogeneity. An elevated RDW has the potential to be a biomarker for prognosis in PE patients. © 2020 John Wiley & Sons Ltd.