Few studies have examined differences in mechanism, presentation, and outcome of trauma in geriatric patients. This study compared pelvic fractures and associated injuries in geriatric and nongeriatric patients. The medical charts of all patients presenting to a large urban emergency medicine teaching program with a pelvic fracture between January 1, 1987 and December 31, 1993 were retrospectively reviewed by study-blinded physicians. Data collected included mechanism and site of injury, associated injuries, disposition (admission or discharge), need for operative repair, length of hospital stay, as well as subsequent deaths and causes. The data were stratified into patients less than 65 years of age (group A) and 65 years or older (group B). Two-hundred five pelvic fractures were reviewed with 85 (41%) in group B. A significantly greater number of pelvic fractures in group B occurred by fall (86% v 25%, P < .05) and significantly less by motor vehicle accident (14% v 75%, P < .05). Site of pelvic fracture differed significantly only in the decreased number of geriatric iliac fractures (6% v 16%, P < .05). The sites of pelvic fractures for geriatric patients in descending order were multiple sites (58%), pubic rami (56%), acetabulum (19%), ischium (11%), iliac (6%), and sacroiliac (2%), and did not differ from nongeriatric patients. Geriatric patients had significantly fewer total associated injuries (40% v 61%, P < .05) although associated chest injuries were significantly more common (21% v 8%, P < .05). Death occurred in three (3%) nongeriatric and nine (11%) geriatric patients. Six geriatric deaths were caused by exacerbation of underlying cardiovascular disease. Geriatric patients underwent significantly fewer operative procedures (6% v 43%, P < .05) but there were no significant differences in the percent admitted (85%) or mean length of hospital stay (9.59 days). Despite the decreased severity of pelvic fractures, care must be taken to prevent morbidity caused by exacerbation of premorbid illnesses in geriatric patients with pelvic fractures.