Abstract: Objective To evaluate the prognostic value of PET／CT in the diffuse large B-cell lymphoma（DLBCL）. Methods All studies published up from January 2000 to March 2015 on the PET／CT in evaluating prognosis of DLBCL were searched from PubMed，Wan fang， Cochrane library， EMBASE，CNKI and Medline database. The STATA11.0 data analysis software was used for meta analysis. The effect of the volume was represented by 95％ confidence intervals （CI）. The efficacy data included the maximum standard uptake value（SUVmax） of the middle phase treatment and the SUVmax and metabolic tumor volume （MTV） at the end phase treatment. A meta analysis of the relationship between prognosis of DLBCL patients with these parameters was performed to generate combined hazard ratios （HRs） with 95％ CI for overall survival （OS） and progression free survival（PFS）. Results Eleven studies， with 1068 patients in total diagnosed pathological types of DLBCL， were included for analysis. In the middle phase treatment （after 2-4 cycles of chemotherapy）， the HR of PET／CT SUVmaxin evaluating the PFS of DLBCL patients was［1.5 （1.12-2.01）， P=0.007］. In the end phase treatment （after 6-8 cycles of chemotherapy）， the HR of PET／CT SUVmaxin evaluating the PFS of DLBCL patients was［1.30 （0.74-2.29）， P=0.369］； the HR of PET／CT SUVmax in evaluating OS was［1.75 （0.74-4.17）， P=0.204］. In the end phase treatment， the HR of PET／CT MTV in valuating PFS of DLBCL patients was［2.17 （1.46-3.24）， P=0.000）］. The HR of PET／CT MTV in valuating the OS was［2.99 （1.91-4.69）， P=0.000］. Conclusion PET／CT SUVmax of middle treatment can be predicted PFS of patients with DLBCL. At the end of the treatment period， MTV of PET／CT can be predicted PFS and OS，but PET／CT SUVmax cannot be predicted PFS and OS.