The rise of economic growth and transport activities worldwide has led to an increase in reliance on vehicles. However, transport activities are associated with several negative impacts, with road safety being a major environmental-societal issue. The main aim of this study is to investigate a possible relationship between investment in road infrastructure and mortality rate due to road accidents. To assess the economic resources invested in roads, the analysis was conducted in two separate groups: middle-income and high-income countries. World Road Statistics 2017, IRF, period 2010-2015, provided data for the analysis of the impact of the economic resources invested in roads, expressed in specific indicators on road casualties. Mortality rate was used as the dependent variable, while the independent variables were: percentage of paved roads, density of the total road network, and proportion of highways. The parameter of economic resources invested in roads is expressed indirectly by the categorization of the middle- and high-income of the countries. In middle-income countries, the provision of a road network increases mobility, and thus the exposure to risk and the possibility of a road accident increases. In high-income countries, the highway network has a significant impact on reducing road accident mortality rate.