AIM:To investigate the frequency of eye disorders in heavy vehicle drivers.METHODS:A cross-sectional type study was conducted between November 2004 and September 2006 in 200 drivers and 200 non-driver persons.A complete ophthalmologic examination was performed,including visual acuity and dilated examination of the posterior segment.We used the auto refractometer for determining refractive errors.RESULTS:According to eye examination results,the prevalence of the refractive errors was 21.5% and 31.3% in study and control groups respectively (P<0.05).The most common type of refraction errors in the study group was myopic astigmatism (8.3%) while in the control group simple myopia(12.8%).Prevalence of dyschromatopsia in the drivers,control group and total group was 2.2%,2 8% and 2.6% respectively.CONCLUSION:A considerably high number of drivers are in lack of optimal visual acuity.Refraction errors in drivers may impair the traffic security.