Abstract: Facility tomato gray mold is a highly harmful and loss causing fungal disease influenced by meteorological factors．Results of years of observation and investigation indicated that, when daily average temperature in facility was ≥14.8 °C, relative humidity was ≥90%, and there was continuous cloudy or low light weather for 10 consecutive days or more, tomato in facility would develop gray mold disease．Tomato gray mold not only causes tomato fruit to rot and drop, resulting in reduced or even no yield, but also affects tomato quality．Based on investigation of disease and pest control and agricultural meteorological experiments, ecological prevention and control measures have been proposed to reduce occurrence of tomato gray mold, such as selecting antiviral varieties and improving meteorological conditions in facilities．