The place of financial deepening in economic growth has always been a subject of attraction to economist and financial experts.  This is in view of its role in mobilizing and allocating resources to various economic units for rapid Economic Growth (EG).  This paper attempts to investigate the extent to which the Nigerian financial sector has played this role between 1990 and 2024.  The time series data obtained from Central Bank of Nigeria statistical Bulletin was subjected to unit root test using Augmented Dickey-Fuller (ADF) to test the stationarity of the data.  Thereafter the co-integration test was carried out and Error Correction Model estimates were obtained.  The result shows that all the independent variables of Credit to Private Sector (CTPS), Market Capitalisation (MKTC), Prime Lending Rate (PLR) and Broad Money Supply (M2) were positive and statistically significant to EG.  It was therefore recommended among others, that the volume of money supply consistent with the growth rate of the economy be worked out and followed religiously.  It was also recommended that the capital market be made attractive to both local and international investors in order to boost market capitalization which is one of the evidence of a deepened financial system.