The construction and the application of cooling and ventilation technology of steel structure silo was introduced. The effect and efficiency of ventilation and cooling of the silo was evaluated by detecting the ventilation parameters such as the fan pressure and superficial gas velocity of the silo. The ventilation mode of the silo was vertical upward press-in ventilation, and the vertical ventilation parameters were measured by digital air pressure and speed meter. The results showed that the unit grain resistance of grain heap increased with the increase of the superficial gas velocity and unit ventilation volume, with positive correlation; in the ventilation resistance, the resistance of the facilities accounted for a larger rate. The central main air duct and the grain delivery channel are designed to share the same pipeline, which was convenient for discharge, but increased the resistance of ventilation facilities and energy consumption. Influenced by the air duct design, the superficial gas velocity of the grain surface in the northeast corner of the silo was low with poor ventilation effect. It is suggested that the main air duct and the branch duct should be arranged radially in the radial direction. After ventilation, the overall temperature of grain heap decreased by 11.3 degrees, and the average temperature of each layer decreased to about -6 centigrade. The effect of aeration-cooling on the grain heap was good except a little part without obvious decrease of the temperature.