This study examined the extent to which traffic volume and road kills changed after rehabilitation of the Lusaka—Mongu highway (M9), which traverses the Kafue National Park. It also assessed the impact of the road kills on the wildlife populations in the park. The study revealed that traffic volume increased by 45% after rehabilitation of the M9 road. Consequently, sighting rates of road kills increased by >50%. The majority of the collisions occurred in the late wet season (January–March). These months coincide with dense vegetation cover and rutting season of impala (Aepyceros melampus), the species that was killed most frequently. Reduced visibility because of dense vegetation cover, and pronounced animal activity during the rut inevitably enhanced chances of wildlife colliding with vehicles. With regard to impacts of the road kills on the wildlife populations, the majority (>86%) of the animals involved in the road accidents are the young and subadults. The collisions, therefore, are affecting the reproductive potential of the species affected. To mitigate against the wildlife-vehicle collisions, the study recommends various measures, such as slashing of verges at the appropriate time, use of speed cameras, and educational and public-awareness campaigns.