Abstract: The study the germicidal efficacy of five chemical disinfectants on the environmental isolated bacteria from the microbiology laboratory could provide a basis for the rational and effective use of disinfectants in the microbiology laboratories. The suspension quantitative germicidal test was used to observe the germicidal efficacy of 75% ethanol, 70% isopropanol, 2 g·L⁻¹ benzalkonium bromide, 400 mg·L⁻¹ 84-aerosol and hydrogen peroxide silver ion disinfectant (4.5 % H₂O₂, 80 mg·L⁻¹ Ag⁺) on the environmental isolated bacteria from microbiology laboratory. The results showed that the killing logarithm values of bacterial propagules exposed to 75% ethanol, 70% isopropanol, 2 g·L⁻¹ benzalkonium bromide and 400 mg·L⁻¹ 84-aerosol for 2 min were all greater than 5.00, which met the requirements of qualified disinfection. When the hydrogen peroxide silver ion disinfectant (4.5 % H₂O₂, 80 mg·L⁻¹ Ag⁺) was used for 60 min, the killing log values of fungi were greater than 4.00, and the killing log values of Bacillus megatherium was greater than 5.74, which met the requirements of qualified disinfection, while the killing log values of Bacillus subtilis was 2.36, which did not meet the requirements of qualified disinfection. In summary, the bacteria isolated from the environment could more truly reflect the microbial contamination in the laboratory. It was suggested that the laboratory should verify the efficacy of disinfectants based on the environmental monitoring data. According to the results of efficacy verification, at least two or more disinfectants should be reasonably screened and used in rotation.