This study primarily seeks to evaluate the influence of financial system stability on economic growth in Nigeria from 1986 to 2016. Employing the use of Principal Component Analysis (PCA), this study constructs a Financial System Stability Index (FSSI) as measurement for financial stability. The indicators used in building the index capture three sectors of the Nigerian Financial System (NFS). The three sectors cover the banking sector, the capital market, the external sector and include a fourth component representing financial depth. The resulting index serves as a single qualitative measure for evaluating the level of stability in a nation’s financial system and proves capable of warning of an eminent financial crisis. Employing the use of four macroeconomic indicators, the index is then regressed against the Nigerian economic growth rate with an aim of discovering the short-run and long-run dynamics existing between both variables. The granger causality test, Johansson Co-integration test and Vector Error Correction Model (VECM) are the estimation techniques employed in achieving the objectives of this research. The granger causality test revealed a uni-directional causality between financial stability and economic growth in Nigeria. The Johansson Co-integration test showed that long-run co-integration relationship exists between financial stability and economic growth. Finally, the VECM results find that financial stability displays a negative relationship with economic growth and bears no significant effect on economic growth in Nigeria. The findings disclose that financial stability in Nigeria may be high and has resulted in the underutilization of financial assets thus hampering sustainable economic growth in Nigeria. In conclusion, the outcome of the findings shows that while financial stability may be necessary for initiating economic growth, it is not sufficient for sustaining economic growth in Nigeria. This research work recommends that the FSSI be employed as an additional tool for measuring the condition/state of financial stability in Nigeria and in predicting the onset of a potential financial crisis. The study further recommends that financial authorities must give attention to other aspects of financial development to facilitate sustainable economic growth in Nigeria.