The invention discloses a temperature detection fixer for a high-voltage power cable intermediate interface, which comprises a mounting plate, a detector is mounted on the mounting plate, sliding grooves are formed in the end surfaces of the two ends of the mounting plate, one end of a supporting plate is slidably clamped in each sliding groove, the other end of the supporting plate is fixedly connected with a connecting plate, and a tensioning mechanism is mounted between the end surfaces of the connecting plate and the mounting plate. The mounting plate clings to the cable interface; the arc-shaped pressing sheet clings to the outer wall of the interface; the supporting plate slides along the sliding groove. Therefore, the connecting plate is moved to cables at two ends of the interface.The connecting plate is quickly clamped and fixed on cables at two ends of the interface through the clamping sleeve; the mounting plate is fixed firmly, the detector is avoided from falling off, theconnecting plate is pulled through the tensioning mechanism, so that the connecting plate slightly moves towards the mounting plate, the weight of the mounting plate is transmitted to cables at the two ends of the interface through the connecting plate, the middle interface below the mounting plate is in a loose state, the middle interface is prevented from being broken and damaged due to pulling, and the detector can conveniently detect the temperature of the middle interface.