Objective To assess the toxic effect of 2% peracetic acid aerosol disinfection on laboratory animals and the staff. Method Isolator was disinfected with 2% peracetic acid aerosol at concentration of 1 g/m^3 density for 4 hours. Rats were kept in the isolator and their behavior and pathological changes were observed to assess whether inspiration of the aerosol lead to toxicity in the rats. Results After 2 % peracetic acid aerosol inspiration for 4 hours, the rats depicted abnormal behavior activity during 4 hours to 7 days. Conclusions 2% peracetic acid aerosolat using a density of 1 g/m^3 is toxic to laboratory animals.