This paper investigates the impact of stock market development on real economic growth in Nigeria. The Johansen Cointegration and vector error correction model (VECM) were used to analyze annual time series data on stock market development indicators and real gross domestic product (GDP) from 1984 to 2018. The results show a long run relationship between stock market development and economic growth in Nigeria. In the long run, market capitalization ratio, all share index and rediscount rate have significant positive effect on GDP, whereas market turnover ratio, and trade openness have strong negative influence on GDP. Results also show evidence of causality effects running from stock market development to real GDP. The paper concludes that stock market development is important for economic growth in Nigeria. The paper recommends that government promote stable economic and political environment, strengthen the regulation and supervision of the stock market, streamline market processes, improve trading system, and increase investment in manufacturing and logistics infrastructure.