Abstract: Temperature field variation rule of carbon fiber reinforced polymer (CFRP) was tested by using electric thermal experimental platform for composites, while revealing the influence mechanism of electric thermal effect on the mechanical properties of CFRP from the interfacial shear strength of monofilament tensile fracture, the short beam shear property and shear fracture etc.The results show that electric thermal effect can increase the overall temperature of CFRP, and reach steady state temperature at about 4 min. CFRP laminate surface temperature is higher with increasing of the current strength, CFRP's surface temperature reaches 151℃ when the current strength is 8 A (0.44 A/mm²); the monofilament tensile and short beam shear strength of the interface with the increasing current strength increase at first and then decrease; when at a low current, the electric thermal effect generates less Joule heat, which can optimize the interface property to improve the interfacial shear strength, when at a high current, the electric thermal effect's Joule heat is much higher, which can produce the irreversible damage such as ablation on interface and reduce the interfacial bonding property.