<p>Properly treated recycled water plays a crucial role in reducing freshwater demand and promoting sustainable water resource management. Despite its significance, public resistance has hindered its widespread adoption over the past few decades and the underlying decision-making mechanisms remain unclear. Based on dual-process theory, this study employs event-related potentials (ERP) technology to examine how various recycled water attributes—water quality, price, odour, and treatment technology– affect public acceptance, alongside the physiological mechanisms underlying these effects. The results indicate that the influence of various recycled water attributes on public acceptance varies significantly. While information regarding water quality, price, and odour, whether positive or negative, does not significantly affect public acceptance, treatment technology demonstrates a substantial impact. Specifically, negative information about treatment technology triggers an initial emotional response, followed by a reflective cognitive process that ultimately leads to rejection. Our heterogeneity analysis further indicates that individuals with greater knowledge of recycled water exhibit weaker emotional and reflective responses, making them less susceptible to negative information and thereby more inclined to accept recycled water. Based on these findings, policy efforts should prioritise the dissemination of positive information about treatment technology, enhance public education, and adopt tailored communication strategies to increase greater acceptance of recycled water.</p>