Underwater artificial freezing device

The invention provides an underwater artificial freezing device. The underwater artificial freezing device comprises an offshore workboat, a hydraulic telescopic rod, a sealing groove box, a freezing mechanism and a water pumping mechanism, the freezing mechanism comprises a rectangular frame, a connecting rod, a freezing pipe body, a brine pump, a refrigeration sheet and a brine tank, the water pumping mechanism comprises a water pump and a water pumping pipeline, after moving to a to-be-constructed area through the offshore workboat, the hydraulic telescopic rod drives the sealing groove box to descend to the to-be-constructed area of seabed soil, the sealing groove box forms a sealing space above the seabed soil, seawater in the sealing space is pumped out through the water pump, then low-temperature saline water is conveyed into the freezing pipe body through the brine pump, therefore the freezing pipe body can abut against the seabed soil for freezing to form a frozen soil curtain, due to the fact that f