With the continuous development and maturity of critical care medicine, the problem of hospital acquired infection(HAI) in the department of critical care medicine has become increasingly prominent. HAI can cause serious adverse consequences, therefore, clarifying its key links and pathogenesis, and exploring more reasonable and effective systematic prevention and control measures are of great significance for reducing HAI in the department of critical care medicine. In addition to systematic prevention and control measures, multidisciplinary collaboration, strong support from administrative departments, and strict implementation of the specific details of HAI prevention and control are also indispensable for properly solving this intractable problem.