This paper analyzes the relationship between socioeconomic status and health inequality in Nigeria using the concentration index, a widely used measure of socioeconomic-related inequality in health. Data from household surveys and health indicators from 1990 to 2022 were used to assess the degree of inequality across different income groups in Nigeria. The findings suggest significant health disparities, with poorer populations experiencing worse health outcomes compared to wealthier stratum. The concentration index revealed that health inequality in Nigeria is pro-rich, indicating high concentration of health outcomes on the illiterate-poor segments relative to the enlightened-rich population. Subsidized medical bills and expansion of medical facilities in the most affected geopolitical zones were recommended.