The invention relates to the technical field of medicine processing equipment, in particular to a cold air system applied to a raw material medicine production workshop, which comprises a constant temperature and humidity chamber, a filter, a centrifugal fan, a plate heat exchanger, a low temperature dehumidifier, a rolling boiling bed, a cyclone dust collector and a wet dust collector, the filter is provided with a fresh air port, one end of the filter is connected with the centrifugal fan, the centrifugal fan is respectively connected with the plate heat exchanger and the low-temperature dehumidifier, the rolling fluidized bed is respectively connected with the low-temperature dehumidifier and the plate heat exchanger, the rolling fluidized bed is connected with the cyclone dust collector, the cyclone dust collector is connected with the wet dust collector, and the wet dust collector is provided with an exhaust port. In practical application, effective control over the temperature and humidity of cold air of the rolling fluidized bed is achieved by applying the system, moisture regain and caking in the production and storage process of the raw material sodium chloride are prevented from the source, the quality of the raw material sodium chloride product is improved, and good economic benefits are achieved.