Abstract: Objective:Primary gastric diffuse large B-cell lymphoma (PGLBCL) is a highly common subtype of extranodal non-Hodgkin lymphoma. We analyzed the disease's clinical features and prognosis to guide better treatment. Methods:We retrospectively collect-ed data from PGLBCL cases seen from January 1999to March 2012in one cancer center. We then analyzed the demographic character-istics, clinical stage, histological diagnosis, complications, treatment, and prognostic characteristics of such patients. Results:A total of 126 patients with median age of 49years old (range: 16- 81years) were included in the study. The male-to-female ratio was 68:58. A to-tal of 96patients were pathologically diagnosed with pure diffuse large B-cell lymphoma (DLBCL),27with mucosa-assouated lymphoid (MALT) component, and 3 with plasmacytoid differentiation. Meanwhile,90% of the patients were in the early stage of the disease. For the early-stage patients, treatment strategy included surgery + chemotherapy ± radiotherapy for38cases, chemoradiotherapy for 39cases, chemotherapy alone for 37cases, and surgery alone for 1 case. Under a median follow up of48months, the 4-year progres -sion free survival (PFS) and overall ourvival (OS) rate of the whole group were 75. 6% and 82. 7%, respectively. PFS rates for early and advanced stage patients were 77% and 41. 7% (P=0. 005 ), respectively. For the early-stage patients treated with chemotherapy alone, chemoradiotherapy, and surgery with therapy, the PFS rates were 67. 3%,77. 8%, and 77. 8% (P=0. 588 ), respectively. The patients with international prognostic index (IPI) score of 0, 1, and > 1 achieved PFS of 85. 4% ,74. 4% , and 55. 6% (P=0. 011 ), respectively. The PFS rates were 81. 2% and 66. 1% (P=0. 018 ) for stages Ⅰand Ⅱ, respectively, and 86. 6% and 63. 3% (P=0. 006 ) for the normal and elevated LDH levels, respectively. The pathological type of pure DLBCL or a MALT component, GCB or non- GCB origin, and age more than 60 years old were not associated with prognosis. Conclusion: The majority of the PGLBCL patients were in the early stage of disease, but the outcome of early- stage disease was favorable. Surgery did not improve outcomes. Univariate analysis demonstrated that IPI score > 1, stage Ⅱdisease, and elevated LDH levels were associated with poor prognosis in the early-stage patient.