Nigeria is Africa’s largest oil producer and a major global crude oil exporter, producing about 1.36 million barrels per day as of 2021. The Niger Delta region, the largest river delta in Africa, serves as the center of the country’s petroleum industry and plays a vital role in its economy. The downstream petroleum sector is particularly important for refining crude oil into usable products that support transportation, industry, and domestic energy needs.Despite its importance, the sector faces major challenges such as low refinery capacity utilization, outdated infrastructure, and heavy reliance on imported refined products. Although Nigeria has four refineries with a combined installed capacity of about 445,000 barrels per day, actual output remains far below expectations due to operational and technical inefficiencies.This study highlights the significance of the downstream petroleum sector in the Niger Delta and examines the constraints limiting refinery performance. It emphasizes the need for improved infrastructure, better management practices, and policy reforms to enhance efficiency and promote energy self-sufficiency in Nigeria.