The invention discloses an EHV and UHV transmission line insulator live-line detection/cleaning integrated robot which comprises a second mechanical arm whose upper part outside is equipped with a hairbrush ring and first and third mechanical arms at two sides of the second mechanical arm. The three mechanical arms share a vertical center surface and are supported and fixed through a fixed base. The first and third mechanical arms can autonomously extend and retract left and right, and the second mechanical arm can move left and right with the fixed seat. The second mechanical arm and any one of the first and third mechanical arms or the three mechanical arms can grasp an insulation steel cap simultaneously to form one or two loops to detect the insulation resistors in the corresponding loops. The insulation steel cap can be holded or loosened through the up and down movements of the three mechanical arms, and the left and right movements of the fixed seat and the left and right movements of the whole robot can be realized through the left and right extension and retraction movements of the first and third mechanical arms so as to detect and clean insulators at different positions.