Objective. To investigate the vascular structure of different malignant tumours of the mandible. Methods. Specimen arteriography was performed on seven cases of squamous cell carcinorma of gingiva and four sarcomas. Results. Maliganant tumours could be divided into two groups: (1) the hypervascular sarcomas in in which the aarteries were dilated, distributed evenly and arranged in a buslike pattern; and (2) hypovascular squamous cell carcinoma with scanty arteries distributed unevenly without dilatation; in some areas, the shape of arteries was irregular and arranged in a network pattern. Conclusions. T he variation in vascular structure of malignant tumours of the mandible may be related to the outcme ofregional chemotherapy. Copyright