Objective To clarify high-touch surface of different departments, provide basis and guidance for cleaning and disinfection. Methods The direct observation method was used to investigate the touch frequency of environmental surface in 5 key management departments of healthcare-associated infection(HAI), including digestive endoscopy room, stomatology department, hemodialysis room, operating room and department of laboratory medicine of a tertiary general hospital in Xi'an, the cumulative touch frequency and touch rate were calculated. Results There were 5-9 high-touch surface in 5 key departments. Touch frequency of high-touch surface in digestive endoscopy room (3.57-13.29 times per manipulation) was significantly higher than those in other departments; touch frequency of high-touch surface in hemodialysis room was 0.56-3.44 times per manipulation, which was the lowest among the 5 departments. Surfaces with high-touch frequency were as follows:diagnosis and treatment bed in digestive endoscopy room (13.29 times per manipulation), manipulation panel on treatment unit in stomatology department (3.64 times per manipulation), touch screen of dialysis machine in hemodialysis room (3.44 times per manipulation), anesthesia computer keyboard and mouse in operating room (8.25 times per manipulation), and computer keyboard and mouse in department of laboratory medicine (4.80 times per manipulation). Treatment trolley was high-touch surface in digestive endoscopy room, operating room, and hemodialysis room. Conclusion Due to different medical manipulation, the high-touch surface of each department is also different. Computer mouse and keyboard, treatment trolley, diagnosis and treatment bed, equipment for diagnosis and treatment, and manipulation unit are all high-touch surface in key departments.