Low-temperature calcium chloride is widely used as the refrigerant medium in freezing construction technology to participate in the process of heat exchange with soil in freezing project.This article introduces an experimental study of obtaining a mixed solution refrigerant with more superior performance by adding certain alcohol organic solvents into the low-temperature brine.Experimental results show that the optimally mixed refrigerant medium brine has lower condensation temperature（-35—-45℃），low density，also has better flow characteristics and carrying capacity in low temperature，which is a perfect refrigerant in freezing construction technology.