<p>This paper proposes the concept of investor stickiness and uses empirical data of listed companies in China from 2007 to 2023 to test the impact of investor stickiness on stock liquidity. We find that: (1) Contrary to intuition, investor stickiness significantly reduces stock liquidity. (2) For state-owned enterprises, the negative correlation between investor stickiness and stock liquidity is weakened. These indicate that investor stickiness is an important factor affecting stock liquidity. Further research shows that assimilation mechanism and game mechanism are important mechanisms by which investor stickiness affects stock liquidity, that is, investors’ adaptability reduces stock liquidity. This paper not only enriches the application of complex adaptive system theory in stock market, but also reveals the adverse effects of investors’ adaptive evolution.</p>