This study examines the relationship between the indices of underdevelopment and poverty in Nigeria by analyzing the effect of key development indicators such as; per capita income, infrastructural development, life expectancy, and educational attainment that served as the independent variables on poverty rate as the dependent variable over the period 1981 to 2025. The study adopts a quantitative research framework and employs time-series data sourced from relevant national and international databases. The Autoregressive Distributed Lag (ARDL) modeling technique is utilized to capture both short-run and long-run dynamics among the variables, given their mixed orders of integration. The ARDL bounds test confirms the existence of a long-run cointegrating relationship between poverty and the selected indicators of underdevelopment in Nigeria. Empirical results show that per capita income has a poverty-reducing effect, particularly in the short run, although its long-run impact is weakened by structural factors within the economy. Infrastructural development exhibits a significant relationship with poverty, but the mixed signs of the coefficients suggest that infrastructure investments have not been sufficiently inclusive or pro-poor. Life expectancy demonstrates a strong and statistically significant negative relationship with poverty in both the short and long run, highlighting the importance of health outcomes in poverty reduction. Educational attainment is found to be significant in the long run, though its limited effectiveness in reducing poverty reflects challenges such as poor education quality and skills mismatch. The study concludes that poverty and underdevelopment in Nigeria are mutually reinforcing. It recommends inclusive growth strategies, improved infrastructure targeting, sustained investment in health and education, and stronger institutional frameworks to achieve sustainable poverty reduction and development.

Keywords: Poverty, Underdevelopment, Autoregressive Distributed Lag (ARDL), Infrastructural development, Nigeria.