Intra-operative radiation therapy (IORT) is a multidisciplinary approach in which residual tumors or tumor beds are directly irradiated during a surgical procedure. To evaluate its efficacy we conducted since 1985 a prospective study including non metastatic gastric adenocarcinoma treated by surgery, IORT (15 Gy) and post-operative external beam radiotherapy (44 Gy). Up to now, 45 gastric adenocarcinomas (18 pNO and 27 pN1N2) have been included in the study. Mortality and morbidity rates were not different from those of surgery alone. Overall 5 year survival rate is 59.1% and pN1N2 5 years survival rate is 50.6%. These promising results are comparable with those of asian randomized studies which demonstrate the possible value of IORT in the treatment of gastric adenocarcinoma.