A Comparative study of preoperative intra-arterial infusion chemotherapy (I.A.) and transcatheter arterial chemo-embolization (TAC-E) was carried out on thirty-eight patients with locally advanced breast cancer. The results were as follows. (1) In the primary lesions, there was no difference in response rate between these two treatment modalities. (2) As for side effects, moderate myelosuppression and gastrointestinal disorders were frequently observed in I.A. group. (3) Considerably lower recurrence rate of visceral metastasis was noted in I.A. group, in comparison with the TAC-E group. After TAC-E, however, there was no local recurrence. (4) Five-year cumulative survival rate of I.A. and TAC-E group were 52.3% and 60.7% respectively, without any significant difference between the two groups. These results indicated that both I.A. and TAC-E were effective preoperative treatment for locally advanced breast cancer. Therefore, we should select each treatment modality considering the patient's characteristics.