The invention relates to a mortar bomb used for fire extinguishing in forest, which is divided into a working part and a propelling part. The working part consists of a fuse, a connecting screw, a medicine package, fire fighting powder, a central slinging medicine pipe, slinging medicine, a shell and a fairing; the pushing part consists of a bomb tail and a basal medicine pipe. The connecting screw of the working part is fixed at the front end of the shell and the front end of the connecting screw fixes the fuse; the central slinging medicine pipe is an acerose metal thin-walled piece that passes through the shell at an axial direction, the front end of which is connected with the fuse through the medicine package and fixed by the connecting screw. The slinging medicine is packed in the central slinging medicine pipe and the fire fighting powder is filled between the central slinging medicine pipe and the shell. The bomb adopts a mortar that is equipped with a large quantity in saturday night soldier reserve components as a launching platform, thus having far slinging distance, high safety performance, high reliability, large medicine packing amount, high fire fighting efficiency and low production and use cost.