The invention, which relates to the technical field of disaster prevention and reduction of the power transmission line, discloses an insulator defect detection method for a power transmission line and terminal equipment. The method comprises: S1, selecting a measurement point; to be specific, selecting the periphery of a power transmission tower as a ground measurement point and selecting a position that is flush with an insulator above the ground measurement point as an aerial measurement point; S2, carrying out visible light measurement and analyzing a visible light shot picture to obtain avisible defect result; S3, carrying out infrared light measurement, analyzing an infrared light shooting picture, and acquiring a difference between axial distribution of an insulator and temperaturedistribution of A-phase, B-phase and C-phase insulators; S4, carrying out ultraviolet light measurement, analyzing an ultraviolet light shooting picture and acquiring an insulator surface discharge condition analysis result; and S5, carrying out defect degree evaluation and positioning, locating a defect position and determining a defect level. Equipment includes a visible light measurement program module, an infrared light measurement program module, an ultraviolet light measurement program module and a defect degree evaluation and positioning program module. On the basis of the five steps,the work efficiency of insulator detection by inspectors is improved.