The invention relates to a solar refrigerating device used for manual freezing of a water-rich loose and soft foundation. A heat collecting system and a steam injecting refrigerating system are included. The heat collecting system comprises a full-glass vacuum heat collecting pipe and a generator; the cylindrical generator is embedded in the tubular heat collecting pipe, and closed heating mediummedia are arranged between the two; and a gravity circulating manner is adopted for the steam injecting refrigerating system which comprises an evaporator embedded in a water-rich loose and soft ground layer, a condenser, a throttling valve, a steam injector, a one-way valve and the like, and the condenser, the throttling valve, the steam injector and the one-way valve are arranged on the ground surface. The device is vertical type refrigerating integrated machine, solar thermal energy and gravitational potential energy are combined for driving a refrigerating agent to circulate, no movement parts exist, consumption of electric energy and mechanical energy is avoided, running is reliable, and the service life is long. The device can be used for reinforcing weak cementation, large hole gapand water-rich unstable ground layers in engineering of excavating, traversing, filling and the like, and is especially suitable for preventing and controlling the hot melting disease of ice-rich foundations in linear engineering of long-distance railways, highways and power transmission lines in permafrost regions.