The invention discloses an anti-freezing system, an anti-freezing heat exchanger and application, and belongs to the field of heat pump systems. The technical problem that under the condition that existing heat exchangers cannot use heat in the outside world during power failure, water pipes in heat exchange pipes are frost-cracked due to freezing is solved. The anti-freezing system comprises an outer pipe. An inner pipe is arranged in the outer pipe. The inner pipe is a hollow elastic hose. Under the condition that water is supplied, the expansion size caused by freezing is offset through shrinkage of the inner pipe during freezing, and the situation that because the outer pipe freezes and is expanded, the outer pipe cracks is prevented. The inner pipe is a silica gel pipe, a rubber pipe or a pearl wool pipe and is low in cost and easy to manufacture. The hollow part of the inner pipe is filled with inert gas, gas tightness and water tightness are good, and the inert gas is safe and good in stability. One end of the inner pipe is a fixed connector, and the other end of the inner pipe is a closed end. The fixed connector is fixed to the outer pipe, and the closed end extends into the outer pipe. By means of the anti-freezing system, the anti-freezing heat exchanger and the application, efficient heat exchange and freezing prevention are achieved, the structure is simple, the price is low, and installation is convenient.