With stearic acid/lauric acid binary of fatty acids as phase change material, polyacrylonitrile (PAN) as framework material, PAN/ binary of fatty acids phase change fibers is prepared by wet spinning process. Morphology and latent heat storage capacity of phase change fibers are investigated using microscope, scanning electron microscope (SEM) and differential scanning calorimetry (DSC), respectively. Influences of the ratio of PAN/ binary of fatty acids, concentration of the coagulation and spinning liquid on breaking strength have been studied by yarn strength tester. The results show that breaking strength of phase change fiber dried at 110°C hot air is higher than that of dried at room temperature, the breaking strength of PAN/ binary of fatty acids fiber increases with the increment of the ratio of PAN/ binary of fatty acids, concentration of the coagulation and spinning liquid. The latent heat storage capacity of phase change fiber has reached 18J/g, the phase transition temperature is about 28.6°C.