The invention discloses a transformer station's safety distance measuring apparatus which comprises a scale joint arranged at one end of a shape fixing hose and two pairs of telescopic scales articulated to the articulation plates fixedly arranged on the scale joint. The two pairs of telescopic scales correspond to the six dimensions of the safety distance of a 10kV power distribution device and a 35kV power distribution device. The other end of the shape fixing hose is connected with a telescopic pipe through screws. The lower end of the telescopic pipe is provided with a wear-resistant protection sheath. The scale joint is provided with an LED light whose switch is arranged at the lower end of the telescopic pipe. The structure of the apparatus is compact and exquisite. The apparatus can be conveniently used and can be manufactured at a reasonable cost. With powerful functions, workmen can use it very conveniently, therefore, increasing their working efficiency.