Objective To compare the environmental microbiological and physical monitoring parameters between the temporary extended medical area and the normal area during the flexible allocation of ward, summarize the rule and find the potential risk points of infection control. Methods From April 10th to 23rd, 2023, prospective environmental microbial monitoring and physical parameter monitoring were carried out in a ward of Zhongnan Hospital of Wuhan University, and the monitoring results under different scenarios were compared and analyzed. Results In general, the carbon dioxide (CO2) concentration, particulate matter 2.5 (PM2.5) concentration, temperature, and relative humidity in the temporary medical area were better than those in the inpatient rooms (P<0.05), but there was no statistically significant difference in the amount of microorganisms detected on the surface of environmental objects or the hands of medical staff (P>0.05). After the start of the temporary medical area, the amount of microorganisms detected on the surface of environmental objects, CO2 concentration, and temperature in the inpatient rooms were higher than those in the temporary medical area (P<0.05), the PM2.5 concentration in the inpatient rooms was lower than that in the temporary medical area (P<0.05), and there was no statistically significant difference in the amount of microorganisms detected on the hands of medical staff or relative humidity between the two areas (P>0.05). Compared with those in the same area when the temporary medical area was not started, in the inpatient rooms after the start, the amount of microorganisms detected in the air, CO2 concentration, temperature, and relative humidity were lower (P<0.05), the amount of microorganisms detected on the surface of environmental objects and PM2.5 concentration were higher (P<0.05), and there was no statistically significant difference in the amount of microorganisms detected on the hands of medical staff between the two periods (P>0.05); in the temporary medical area after the start, the PM2.5 concentration was higher (P<0.05), the CO2 concentration and temperature were lower (P<0.05), and the differences in the relative humidity and amounts of microorganisms detected on the surface of environmental objects and the hands of medical staff between the two periods were not statistically significant (P>0.05). Regardless of whether the temporary medical area was activated or not, Filamentous fungi had the highest detection rates in air samples, and Staphylococcus epidermidis had the highest detection rates in both environmental surface samples and medical staff hand samples. Conclusion A series of environmental risks such as environmental microbial load and poor ventilation caused by temporary medical areas should be paid attention to.