Caliper for measuring gradient of power transmission line tower

The invention discloses a caliper for measuring the gradient of a power transmission line tower, and the caliper comprises a bearing assembly which comprises a bearing disc, wherein the surface of the bearing disc is symmetrically and fixedly connected with L-shaped supporting rods in an inserted manner, the end parts of the L-shaped supporting rods are fixedly connected with a positioning plate, and the positioning plate is detachably fixed on the power transmission line tower through a fixing mechanism; a caliper assembly which comprises an installation opening formed in the bearing disc, wherein a fixing shaft is fixedly inserted into the installation opening, the middle of the fixing shaft is movably sleeved with a caliper structure, and the caliper structure is movably connected with the fixing shaft through a bearing; the fixing shaft is movably sleeved with swing arms located on the two sides of the caliper structure, a telescopic rod is horizontally and fixedly connected to the end of the swing arm on