The invention discloses a multifunctional full-automatic gas charging device of SF6 equipment and relates to the technical field of devices for charging compressed gas. The device comprises an SF6 gas cylinder and an electric control cabinet. The electric control cabinet comprises a cabinet body. The cabinet body is provided with a gas inlet and a gas outlet. A gas outlet of the SF6 gas cylinder is connected with the gas inlet of the cabinet body. The gas inlet of the cabinet body is connected with the gas outlet of the cabinet body through a pipe. An electric control panel is further arranged in the cabinet body. The electric control panel comprises a microprocessor, a gas cylinder side temperature and pressure intensity sending module, an equipment side temperature and pressure intensity sensing module, a proportional solenoid valve, an environmental information sensing module, a man-computer interaction module, a prompt module and a power module. The device can automatically complete gas charging of the SF6 equipment, the working efficiency is improved, gas charging is controllable, and precision is high.