Abstract: The concentrations of carbon dioxide， hydrogen sulfide， ammonia and meteorological factors were monitored using online detection equipment for one year in Tianziling landfill. The results showed that the concentration of odor was higher from 6 p.m. to 6 a.m. This may be due to the low wind speed and the existing of inversion layer in the night times. The odor concentrations were the higher from January to May and October to December. Combined with the analysis of meteorological data， the reasons for the higher odor concentration may be related to wind speed， wind direction， temperature and pressure， but not related to humidity.