Abstract: Due to the influence of various external weather conditions, power overhead lines have different effects on quantum signals than that of public network communication lines. This test is to detect the stability of the QKD system of various encoding technologies and its quantum states under natural environmental conditions such as breeze vibration, galloping, various meteorological conditions, and line icing when passing the overhead OPGW. Through the field tests in two kinds of outdoor environments show the phase-coded QKD is given as the most suitable quantum security communication technology for power communication lines. It qualitatively analyzes the stability of quantum signals when they are transmitted through power communication networks.