Purpose:After car accident,motorcycle accident ranks as the second leading cause of traffic fatality in Iran.This study aimed to compare the severity and clinical presentations between drivers and passengers under the same injury circumstance.Methods:This study was conducted in the trauma center of Shiraz,Iran in 2017.Data on demographics,triage level,blood pressure,respiratory rate,Glasgow coma scale (GCS),injured body region,injury severity score (ISS),revised trauma score (RTS),and result of accident were compared between pairs of drivers and passengers.The agreement of any type of injury between drivers and passengers evaluated by Kappa test.Results:This study included 143 matched pairs of drivers and passengers.Most of the pairs (84.5％) did not use helmet and 772％ of the riders do not have driving license.ISS was significantly higher in drivers than passengers.In the unmatched pairs,drivers and passengers showed no difference in sustaining injuries in the face,head & neck,chest and soft tissue,but drivers were found more likely to suffer from injuries in the abdomen,extremities,pelvis and spine than passengers.Once one part of the matched pair suffered injury in the head & neck,face,chest,abdomen,extremities and soft tissue & skin injury,the probability that the other part had an injury in the same region was 50％,9％,13％,7％,22％ and 34％respectively.Kappa value for these body regions was 0.006,0.009,-0.006,0.068,0.063 and 0.001,respectively,which was significant in abdomen and extremities.Conclusion:Although drivers had higher level of injury severity and some different injury distributions,we recommend equal treatment to drivers and passengers.We also recommend related authorities to develop policies on helmet use,driving license and third-party insurance.