As China’s economic and social development gradually enters a high-quality development stage characterized by green and low-carbon transformation, enterprises, as the core actors of economic activities, bear significant responsibilities in ecological and environmental governance. Based on the 2016 Chinese Private Enterprise Survey data, this study employs the XGBoost model combined with SHAP value analysis to explore the impact of CEO capital characteristics (educational level, age, overseas experience, and political capital) on corporate pollution control investment. Furthermore, the study examines the mechanisms of the institutional environment. The findings reveal that CEO capital characteristics significantly influence corporate pollution control investment, but the effects vary across different traits: CEOs with higher educational levels are more inclined to increase pollution control investment, the impact of age on pollution control decisions shows heterogeneity, while the influence of overseas experience and political capital is limited. Additionally, the institutional environment plays a crucial role in corporate pollution control decision-making, guiding enterprises to optimize their environmental behavior through environmental regulations, social supervision, and market incentive mechanisms.