We studied the mortality of amphibians and reptiles due to motor vehicles in asegment of 2.4Km along the Buga-Buenaventura road. This road crosses the ForestalReserve Bosque de Yotoco, a fragment of Sub-Andean forest in the western Andes ofColombia. We also recorded the variation in composition and structure of herpetofaunalassemblages from areas close to the road versus areas away from the road (forestinterior). We found a mortality rate of one vertebrate every 3-4 days; 50% wereamphibians, mostly reptiles (snakes, 0.047 individual/day/Km). Amphibians appearedto be more susceptible than the reptiles to road disturbance. Amphibian richness washigher away from the road, in areas of forest interior (seven species) than in areasclose to the road (four species), while reptiles exhibited an opposite pattern (twelvespecies close to the road versus eight species in the forest interior). Five species ofamphibians and reptiles were recorded exclusively in areas near the road, fi ve speciesexclusively in the forest interior, and eleven species in both areas. We discuss changesin distribution of species as a consequence of alteration in microclimatic characteristicsand vegetal complexity in areas in proximity to the road, but other factors may havean infl uence as well (e.g., noise, pollution).