The SF6 gas density meter is a pointer instrument arranged in the substation to measure the density state of the SF6 gas which is the arc extinguishing medium of circuit breaker. In order to solve the problem that the traditional pointer meter is difficult to apply in the substation automation management, this study proposes a remote meter reading system for substation SF6 gas density meter based on LoRa wireless communication technology and machine vision, and carries out the system’s overall design, hardware design, and software design. This design can achieve remote automatic management of the substation pointer SF6 gas density meter in a high efficiency, low power consumption, and low cost way. This system has clear functions, convenient layout, easy expansion, and low maintenance cost. It has a very important reference value for the application of substation automation management.