Provided according to one embodiment is a device for sensing a gas, comprising: a lamp for outputting ultraviolet light; a first PCB including a hole for inserting the lamp; a second PCB disposed perpendicular to the first PCB and including a lamp power terminal and a lamp ground terminal used to supply power to the lamp; a third PCB disposed parallel to the first PCB, disposed perpendicular to the second PCB, and including a power reception terminal for receiving power from the outside; a first ring-shaped electrode attached to the lamp power terminal and fixing the lamp; and a second ring-shaped electrode attached to the lamp ground terminal, fixing the lamp, and disposed parallel to the first electrode.