Nigeria, a sub-Saharan African nation, is endowed with an abundance of natural resources, particularly those needed for industrial purposes. Despite this, the present level of output in the industrial sector in Nigeria is too low, particularly when it comes to investment undertaking by corporate investors. Therefore, the study examined the effect of stock market integration on industrial corporate investment in Nigeria from 1986-2023. Data used were sourced from the Central bank of Nigeria Statistical Bulletin. The study used Augmented Dickey-Fuller (ADF), bound test and Autoregressive Distributed Lag. The ADF estimate indicated that money supply and all share index were integrated of order one; while, corporate investment, stock market integration, real exchange rate, and lending interest rate were integrated of order zero. The F-value for the bound test estimate was much higher than upper bound of critical value at 5% conventional level; therefore, suggesting a long-run link between the use variables. The short-run estimates showed that stock market integration, real exchange rate and all share index were significant with direct effect on corporate investment; while, money supply and lending interest rate were significant also with indirect effects. Furthermore, long-run estimate showed that money supply and all share index were significant with direct effect on corporate investment; while, real exchange rate and lending interest rate were significant with indirect effects. This suggests that stock market integration currently witnessing in Nigeria is tentative. The study concluded that the current growth witnessing by industrial corporate investment in Nigeria due to stock market integration is not sustainable. Therefore, recommended that the Nigerian Exchange Group’s management should ensure that stock market price exhibit low volatility rate by making sure that its stocks management policies reflect best global stock exchange practice.