In this paper, the cryoballoon used for the treatment of benign airway stenosis was tested under different inlet pressures, different loads and precooling conditions. The results showed that the temperature of the cryoballoon surface decreased as the intake pressure increased, but the temperature did not decrease significantly at 700Psi. With direct throttling, the cryoballoon could only form 1.6mm ice in pork liver. Using precooling and then throttling, ice sheets of 3mm and 4mm were formed in pork liver at 600Psi and 700Psi inlet pressures.