Good law and governance are important ways to enhance the investment expectations and investment confidence of entrepreneurs. Few studies provide micro-evidence that the improvement of judicial quality affects the investment decisions of enterprises from the perspective of environmental justice. Based on the data of listed companies in China from 2003 to 2020, this study investigates the impact of environmental judicial specialization on enterprise investment behavior by using the differences-in-differences method. The results show that the establishment of environmental courts could boost the expansion of the investment scale of enterprises, which is driven by the increase of environmental protection investment and R&D investment of enterprises. Mechanism analysis shows that the investment-driven effect of the establishment of environmental courts is mainly achieved by alleviating the financing constraints of enterprises and reducing the degree of information asymmetry. Further analysis shows that the investment-driven effect of the establishment of environmental courts is more obvious in heavily polluting industries, enterprises without political affiliation, and non-national environmental protection model demonstration cities. In addition, the establishment of environmental courts could not improve the value and investment efficiency of the enterprise. This study provides detailed micro evidence for clarifying the debate on whether environmental regulation and enterprise investment are in conflict or coordination, and offers enlightenment for further improving the specialization of environmental justice and promoting the high-quality development of enterprises.