Over time, technological advancement and industrial development have caused severe threats to our environment. Almost all countries are affected by a surge in environmental issues. The GCC countries were also influenced by increased production over a number of years, contributing to increased carbon emissions. In line with this argument, this study aims to examine the dynamic nexus among stock markets, environmental quality, and energy consumption across the GCC countries, using the sample from 1990 to 2020. We apply both ARDL and nonlinear ARDL techniques to examine the effect of stock market development on environmental quality. Regarding the linear relationship, this study reports that energy consumption and population density are the statistically significant factors of environmental quality in the short run. In contrast, energy consumption, stock traded, economic growth, and population density are robust predictors of environmental quality in the long run. However, our analysis finds no nonlinear relationship between stock market development and CO2 emissions. Results of the causality test show that bidirectional causality flows between energy consumption, economic growth, population density, and environmental quality.