A portable fire extinguishing apparatus, which comprises a casing (20) and a cartridge (3) arranged inside the casing (20). The top end of the cartridge (3) is fixedly connected with the casing (20) through a snap ring (24); the bottom of the cartridge (3) is fixedly connected with the casing (20) through some nuts and bolts; and an explosion venting unit (2) is arranged at the jet end of the cartridge (3). Kinetic energy generated from explosion is consumed through shifting and limiting processes of the explosion venting units (2), therefore recoil force or forward impact force generated after explosion of explosives can be consumed or released, so that safe and effective explosion venting is achieved and hurt to human bodies or articles after explosion of grains is avoided.
