OBJECTIVE: This study aimed to compare Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST) 1.0 and Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 of treatment response with end-of-treatment 18F-FDG PET/CT after first-line chemotherapy for malignant lymphoma. METHODS: This retrospective study included 41 patients with malignant lymphoma. 18F-FDG PET/CT examinations were performed before and after the first-line chemotherapy. Therapeutic results were classified to complete metabolic response(CMR), partial metabolic response(PMR), stable metabolic disease(SMD) and progressive metabolic disease(PMD) according to PERCIST 1.0, complete response(CR), partial response(PR), stable disease(SD) and progressive disease(PD) according to RECIST 1.1. Therapeutic response evaluation was performed according to both PERCIST1.0 and RECIST1.1.The therapeutic response rates (CMR/CR+PMR/PR) were calculated. The concordance between the two criteria was analyzed using Wilcoxon signed-rank test. Cohens Kappa coefficient and Chi-Square test were used to assess the agreement and therapeutic response rates between the two criteria. The curves of progression-free survival (PFS) were calculated by the Kaplan-Meier method, and their significance was calculated by the log-rank test. RESULTS: In PERCIST1.0 analysis,12 patients had CMR,21 20 patients had PMR, 7 patients had PMD,and 1 patient had SMD. In RECIST1.1 analysis,5 patients had CR,34 33 patients had PR ,1 patient had SD and 1 patient had PD.There was no significant difference in response classification between the two criteria(Z=-0.832, P>0.05). There was significant difference between therapeutic response rate with PERCIST1.0 and RECIST1.1(χ2=8.673, P<0.05) (χ2 = 8.421, P<0.05), 80.49% (3332/4140) vs. 95.12% (3938/4140) respectively. There was 14.63% (6/41) disagreement found with a fair agreement (κ=0.349, P<0.05),because the 6 patients with PR were classified to SMD by PERCIST1.0. There was significant difference between the two criteria for distinguishing CR/CMR from PR/PMR(χ2=4.849, P<0.05) (χ2=4.567, P<0.05), and 27.27% (9/33) disagreement was found in therapeutic response assessment, with a fair agreement(κ=0.327, p<0.05). There was a significant difference in PFS outcomes according to PERCIST1. 0 (χ2=14.980, P<0.005). Patients achieving PMR had significantly improved PFS[(18.25 ±4.62)months] than SMD[(13.14 ±6.20)months] (χ2=8.567, P<0.005). CONCLUSIONS: PERCIST1.0 maycan be more accurate evaluating chemotherapeutic response rate in malignant lymphoma than RECIST1.1, and PERCIST1.0 can distinguish PMR from CMR accurately, and effectively predict survival in patients with malignant lymphoma.