This study examined the impact of financial deepening on economic growth in Nigeria from 1980 – 2022, to achieve the objectives, the study examined the impact of market capitalization ratio to gross domestic product, money multiplier to gross domestic product, ratio of broad money supply to gross domestic product and ratio of total bank credit to private sectors in Nigeria. The data were obtained from Central Bank of Nigeria statistical bulletin (2024) and analyzed using the error correction methodology (ECM). The result shows that market based capitalization ratio, money multiplier to gross domestic and ratio of broad money supply to gross domestic product had direct and significant impact on the economic growth rate in Nigeria. Therefore, the study recommends that government policies should be directed towards improving the capital market functioning, improving credits mobilization towards the private sectors as well as increasing and ensuring appropriate money supply injections that would help to sustain the temple of economic growth rate as inspired by the financial deepening in the Nigerian economy.