Abstract: Precooling of fruits and vegetables is one of the primary links in the cold chain. A 100 t cold storage was used as the research object, and the mathematical models were established for both the air and the fruit and vegetable zones; the k-ε turbulent model and the unsteady state solution method were taken into consideration, and then the computational fluid dynamics software was used to carry out the numerical simulation of three-dimensional unsteady state for the precooling process of the fruit and vegetable. When other parameters were assumed to be constant, the temperature field distributions induced by different wind velocities and air supply modes were compared and analyzed. The results showed that the air supply velocity had a significant impact on the temperature field of cold storage, the temperature decreased with the increase of the wind velocity, and the temperature gradient gradually decreases; the two air supply modes were compared, and the uniformity of precooling was better while mode of the upper air supply and lower air return was adopted.