Rechargeable household combustible gas alarm device

The utility model discloses a rechargeable household combustible gas alarm device, which comprises an upper shell, a lower shell and a detection circuit board, the upper shell and the lower shell are detachably connected and enclosed to form a hollow mounting cavity, the detection circuit board is mounted in the mounting cavity and is electrically connected with a combustible gas sensor, a lithium battery is mounted on the lower shell, and the detection circuit board is electrically connected with the combustible gas sensor. The lower shell is installed on the installation backboard, the installation backboard is connected with the lower shell through a buckle, a light guide hole is formed in the upper shell, the light guide column shielding cover is of a hollow structure, one end of the light guide column shielding cover is communicated with the light guide hole, a light guide column is inserted into the light guide column shielding cover and extends to the light guide hole, and an alarm indicator lamp is ar