Objective：The retrospective analysis was conducted to study the effectiveness of radiotherapy for the patients with AIDS related primary cerebral lymphoma. Methods： From January 1995 to December 1999, 8 patients with AIDS related primary cerebral lymphoma were treated in Department of Radiotherapy, Henri Mondor Hospital, Medical College, University Ⅻ of Paris. Median age was 32 years (range: 21－ 57 years). Eight patients received irradiation of 30 Gy to total brain, 4 patients continued to receive irradiation of 15－ 20 Gy to the primary cerebral tumor. The median dose of radiotherapy was 37.5 Gy (30－ 50 Gy). Results： After radiotherapy, the tumor size in brain was reduced in 4 patients, did not change in 3 patients, and increased in 1 patient. The median survival was 7.1 months (range:3－ 19 months). Conclusions： There was poor survival for the patients with AIDS related primary cerebral lymphoma and radiotherapy could prolong the survival of the patients.