Disarticulated mandibles from prehistoric Aleutian sea mammals showed three general categories of paleopathology: (1) lesions imposed on the dentition and surrounding bone by bacteria and their by-products observed in 13 of 49, (2) lesions associated with periodontal disease observed in 14 of 49, and (3) lesions associated with mechanical attrition in 6 of 49. The sea mammal bones obtained from prehistoric eastern Aleutian village refuse middens suggest that younger and possibly weakened or old animals were preferentially captured by the Aleuts, although it remains to be determined the actual proportion of young to old, and the proportion of sick to healthy, in the natural populations. Radiography may be useful to determine the extent of dento-alveolar abscesses and periodontal disease in the absence of soft tissues for examination.