The invention discloses a method and a device for drying vegetables at a freezing point. The method comprises the following steps of: (1) raw material classification, inspection, cleaning, peeling and segmentation; (2) quick blanching; (3) quick cooling; (4) quick freezing; (5) temperature control and drying; and (6) packing and storage. The device for drying the vegetables at the freezing point comprises a sealed drying chamber, a cooling device and an air drying device are arranged in the drying chamber, and an air flowing acceleration device is arranged in the drying chamber. The vegetables are quickly frozen through the cooling device, the air in the drying chamber flows circularly through the air flowing acceleration device, and the drying device absorbs moisture in the circular flowing air so that the moisture in the vegetables is reduced to a limit that microbes cannot be propagated or move, the activity of enzyme in the vegetables is inhibited and a product can be stored for a long term.