The objective of this study was to evaluate the risk factors and in-patient cost of traffic injury. A total of 233 crash victims, 134 non-traffic trauma patients and 87 non-trauma patients admitted to the surgical units of the Kenyatta National Hospital between February 1, 1999 and April 30, 1999 were enrolled in the study. Information on age, gender and occupation of the patient, payer category, alcohol use, length of hospital stay, hospital cost and principal region of injury was gathered. Road trauma admissions comprised about 31% of all admissions due to injury, 15.1% of surgical admissions and 4.5% of emergency hospital admissions. The male sex, occupation status and regular use of alcohol appeared to be significant risk factors for injury occurrence. The respective hospital costs for non-traffic trauma patients and non-trauma patients were 2.2 and 1.9 times higher as compared to road traffic accident trauma patients. The capacity of the injured to compensate for the care given was minimal. In only 6% of the road traffic accident patients was the hospital bill cleared through a health insurance agency or medical scheme. It is concluded that road traffic injury is common, costly, places considerable workload on the hospital and referentially occurs in productive males. It is suggested that the current orientation of trauma care delivery cannot be sustained. Cost containment strategies including the re-examination of the national health insurance scheme may be the way forward to reduce the cost of injury.