Objective To explore the application effectiveness of multi-dimensional process management mode in healthcare-associated infection (HAI) management in intensive care unit (ICU). Methods ICU inpatients at the First Affiliated Hospital of Xiamen University from January 2023 to December 2024 were selected as the research subjects. Based on whether the multi-dimensional process management mode was implemented for strengthening HAI prevention and control, patients were divided into pre-intervention group (January-December 2023) and post-intervention group (January-December 2024). The effectiveness of HAI prevention and control between two groups were compared in terms of hand hygiene compliance rate, incidence of HAI due to invasive procedure, and infection rate of multidrug-resistant organism (MDRO). Results After implementing the core strategy of "multi-dimensional process management mode", hand hygiene compliance rate of healthcare workers (HCWs) in post-intervention group was higher than pre-intervention group (96.25% ［616/640］ vs 66.77% ［414/620］), difference was statistically significant (χ²=183.37, P<0.001). Daily incidence of catheter-associated urinary tract infection (CAUTI) in post-intervention group was lower than pre-intervention group (0.40 ‰ vs 2.18 ‰, P<0.05). Daily incidences of central line-associated bloodstream infection (CLABSI) and ventilator-associated pneumonia (VAP) in pre-intervention group were 0.48 ‰ and 2.26 ‰, respectively, while those in post-intervention group were 0.19 ‰ and 1.12 ‰, respectively. The values decreased slightly, and the differences were not statistically significant (both P>0.05). The MDRO infection rate in patients after intervention was lower than before intervention (2.15% ［22/1 023］ vs 4.20% ［47/1 120］), difference was statistically significant between two groups (χ²=9.87, P<0.05). Conclusion ICU have achieved effective results in multiple key aspects of HAI prevention and control through system planning, multi-dimensional process management mode construction, and continuous quality improvement, providing a scalable practical paradigm for infection prevention and control in the field of critical care medicine.