The utility model relates to a supporting structure for fixing high -pressure test wire, including support piece, at least three insulator spindle and mounting. The high pressure test wire can set upon support piece, and the one end of insulator spindle sets up in the backup pad, makes the backup pad to keep away from ground through the insulator spindle, and then makes the unsettled ground of leaving of high -pressure test wire. Can support the backup pad steadily through at least three insulator spindle, keep away the activity of support -free board, improve the stability that supports high-pressure test wire. The mounting is used for cliping high -pressure test wire and fixes at support piece, and then avoids high -pressure test wire to remove or drop influence test personnel's the safety and the stability of test result.