Objective: To investigate the prognostic role of nutritional status indices including control nutritional status (CONUT) score and prognostic nutritional index (PNI) in patients with diffuse large B cell lymphoma (DLBCL). Methods: The clinical data of 105 patients with DLBCL at the affiliated Huaian No.1 People's Hospital of Nanjing Medical University were retrospectively collected. And the patients' CONUT score and PNI were calculated. The cut-off values of CONUT score and PNI were determined by ROC curves. CONUT score and PNI were grouped with 6.5 and 47.28 respectively. Kaplan-Meier survival analysis, univariate and multivariate COX regression analysis and Spearman correlation analysis were performed sequentially. Results: K-M survival curves demonstrated that CONUT score and PNI have a predictive effect on patients' OS (P < 0.05). Univariate analysis showed that CONUT score, PNI, IPI risk score, albumin, absolute lymphocyte count, and cholesterol were prognostic factors for patients' OS. The results of multivariate analysis showed that CONUT score had an independent prognostic effect on OS in DLBCL patients (HR=2.742, 95% CI 1.030-7.300, P<0.05) and PNI (HR=0.526, 95% CI 0.135-2.047, P=0.35) was not an independent prognostic factor for patients' OS. Correlation analysis showed a high negative correlation between the two nutritional status indicators (r=-0.79, P<0.01). Conclusions: CONUT score is an independent prognostic factor for DLBCL patients, and the higher the patient's CONUT score, the worse the prognosis.