This study examines the impact of public capital expenditure and the role of institutional quality in Nigeria. It employed annual time series data from 2002 to 2022, sourced from the World Bank Development Indicators (WDI, 2023) and the World Governance Indicators (WGI, 2023). The methodology adopted was the Fully Modified Ordinary Least Squares (FMOLS). The data were subjected to a unit root test (ADF), and all variables were found to be integrated at either I(1) or I(0). The FMOLS results revealed that the negative impact of corruption on public capital expenditure (PCE) is masked by political priorities. The error correction mechanism (ECM) indicates a speed of adjustment of 59%, capable of correcting disequilibrium annually. Based on these findings, it is recommended that the government strengthen legal institutions, combat corruption, and promote political stability to ensure efficient and sustainable public investments.