Objective To investigate whether the intensive care unit (ICU) is still a high-risk unit for healthcare-associated lower respiratory tract infection(HA-LRTI)caused by multidrug-resistant Acinetobacter baumannii (MDR-AB) when infection prevention and control measures are implemented. Methods HA-LRTI caused by AB in a hospital from August 2017 to August 2018 were investigated, patients with MDR-AB infection were selected as case group, with sex and age±2 years old as matching factors, a 1:1 matched case-control study was adopted, patients without MDR-AB infection during the same period were selected as control group, logistic regression was used to control other confounding factors, whether ICU was still a high-risk unit for MDR-AB HA-LRTI was explored. Hand hygiene of health care workers(HCWs) in ICU and general wards during the same period was investigated and compared. Results A total of 227 patients confirmed with HA-LRTI caused by AB, including 66 cases of MDR-AB infection and 161 cases of non-MDR-AB infection. After 1:1 matching,binary antimicrobial use before infection, urinary catheterization days and central venous catheterization day in petients in control group were all higher than those in case group (all P<0.05); ICU occupancy rate, central venous catheterization rate and urinary catheterization rate in patients in case group before infection were all higher than those in control group (all P<0.05); logistic regression analysis showed that ICU stay and urinary catheterization were independent risk factors for MDR-AB HA-LRTI (both P<0.05). Resistance rates of AB to cefuroxime/sulbactam in patients in case group and control group were both >90%, and the sensitivity rates to polymyxin B were all 100%. Hand hygiene compliance rate of HCWs in ICU was higher than that in general wards (86.96% vs 71.94%, P<0.05). The awareness rate of hand hygiene knowledge of HCWs in ICU was also higher than that of general wards (90.77% vs 84.47%, P<0.05). Conclusion ICU is a high-risk unit for MDR-AB HA-LRTI, patients with urinary catheterization are the high-risk population for MDR-AB infection.