The invention discloses an electricity saving method of communication engineering, and relates to the technical field of communication engineering. The electricity saving method comprises the steps that S1, an electricity saving box is installed, wherein the electricity saving box is internally provided with an information collector, an information processor, an information amplifier, a low-voltage DC power supply and a high-voltage DC power supply, an electronic change-over switch is installed between the low-voltage DC power supply and the high-voltage DC power supply, and the output end of the information processor is connected with the electronic change-over switch; and S2, the information collector is connected to a terminal with communication engineering equipment, wherein the information collector transmits collected information to the information processor, the information processor carries out information amplification processing through the information amplifier, and the information processor controls an electronic contact of the electronic change-over switch according to processed information conditions so as to select the low-voltage DC power supply or the high-voltage DC power supply. The electricity saving method disclosed by the invention facilitates to realize quick collection, processing and control of information, and can achieve an effect of electricity saving.