Objective To research and analysis in the hospital respiratory medicine haze weather pathogen detection and disinfection effects. Methods From February 2015 to February 2016, a total of 20 haze weather days were chosen as observation group, and another 20 sunny weather days were selected for control group at the same period. In two groups in Tangshan worker's Hospital Respiratory Medicine Clinic, the suffering from pathogenic bacteria was detected, and the same disinfection effects of ward were compared. Results Before disinfection, the number of bacteria in air in the observation group was (2 719±152)cfu/m3, while the control group was (2667±167)cfu/m3, and there was no difference between the two groups (P>0.05). But the observation group concentration of floating dust (0.523±0.122)mg/m3, significantly higher than (0.373±0.055)mg/m3 in the control group (P<0.05); after disinfection of observation group, the air number (497±94)cfu/m3, concentration of floating dust (0.185±0.037)mg/m3, were significantly higher than (408±81)cfu/m3, (0.091±0.038)mg/m3 in control group (P<0.05); before disinfection, air bacteria was not significantly different, in the observation group, air bacteria at noon and afternoon after disinfection (497±94)cfu/m3, (633±79)cfu/m3, were significantly higher than (408±81)cfu/m3, (561±66)cfu/m3 of the control group (P<0.05); after air purification, the air concentration of dust in the observation group were (0.503±0.105)mg/m3 in morning and (0.331±0.084)mg/m3 in afternoon, were significantly higher than those in control group [ (0.262±0.067)mg/m3, (0.285±0.094)mg/m3], and the differences were statistically significant (P<0.05). Conclusions The detection rate of pathogenic bacteria in the respiratory medicine of the fog and haze days is significantly higher than that in the fine weather, and the disinfection effects is significantly lower than that of the fine weather, the length and rate of disinfection should be increased in fog and haze days. Key words: Outpatient clinics, hospital; Respiratory medicine; Fog and haze weather; Pathogenic bacteria detection; Disinfection effect