The invention discloses an automatic alarm device with a fire smoke detection function, which comprises a fixing device, a gas collection device, a detection device and a guide device, wherein the fixing device comprises a base and a shell, one side of the shell is fixedly connected with one side of the base, the base is provided with a plurality of fixing holes, the gas collection device is connected with the shell, the detection device is connected with the shell, the guiding device is movably connected with the shell, the shell is sequentially provided with an air inlet channel and a mounting groove from bottom to top, the air inlet channel is communicated with the mounting groove, the air collecting device comprises a miniature air pump, a jacking air bag and a sealing block, the sealing block is arranged in the air inlet channel, an airflow inlet is formed in the lower end of the air inlet channel, the jacking air bag is arranged at the airflow inlet, and an airflow channel is formed in the jacking air bag and is communicated with the air inlet channel. The bottom side of the sealing block is connected with the outer side of the jacking air bag, the diameter of the sealing block is gradually changed, the sealing block is in a drop shape, a micro air pump is arranged in the mounting groove, and the air inlet end of the micro air pump faces the upper end of the air inlet channel.