Abstract: A feasible conductivity method of measuring the crystallization temperature of mold flux was proposed to solve the limitations of the existing measuring methods.At first,the relationship between the activation energy and compositions of precipitates as well as the ratio of crystallization was analyzed theoretically.Then a simple measuring method was developed based on the former theoretical analysis.The measuring results were verified by differential thermal analysis(DTA),polarizing microscopy and X-ray diffraction analysis.It is shown that this measuring method has high accuracy and low cost,and the determination of main precipitates is basically right,indicating that this method can be a new means studying the crystallization temperature of mold flux.