Abstract: Objective To investigate the association of the level of mir-27a and the prognosis of diffuse large B cell lymphoma (DLBCL) and assess its prognostic value. Methods Micro-arrary expression profiles and clinical data of 116 patients with DLBCL were downloaded from gene expression omnibus (GEO) database. The overall survival (OS) of patients with high and low mir-27a expression levels were compared by Log-rank test.Univariate (international prognostic index, IPI or mir-27a) and multivariate (IPI+mir-27a) Cox proportional hazards models were constructed and time-dependent receiver operating characteristic curves (ROC) method was used to evaluate the predictive power of the model over time. The overall prediction accuracy of each model was evaluated and compared with the consistency statistic C. Results The high expression level of mir-27a was a protective factor for the prognosis of patients with DLBCL (HR=0.24, 95% CI:0.070-0.855, P=0.028). The C statistics of the univariate and multivariate models were significantly difference (IPI vs. IPI+mir-27a:Z=10.719, P<0.001; mir-27a vs. IPI+mir-27a:Z=11.189,P<0.001). Conclusions The high expression level of mir-27a is a protective factor for the prognosis of DLBCL patients. The predictive accuracy of DLBCL patients may be elevated through integrating mir-27a with IPI.