The invention relates to a gas cylinder transfer device, including a device rack with air cylinder pass opening on the front end. Front end fence is spliced through hinged structure on the cylinder pass opening on the device rack. The front end fence has opening position for dismantling gas cylinder with hinged structure rotation as well as stopping position in hinged structure rotation for preventing the charged cylinder from falling forward. Cylinder transfer device also includes lock structure which maintains it when the front end fence is maintained in the opening position. When the front end fence is in opening position, lock structure makes the front end fence remain in the opening position to avoid falling of front end fence when loading the cylinder into the transfer device or unloading it from transfer device. It avoids the inconvenience of loading and unloading due to the possibility of falling as the front end fence is unstable in opening position through existed technology. And it would easily injury handling personnel and cause potential safety hazard. Or it needs specialized personnel to hold it by hand so as to occupy labor resources.