To provide a fire extinguisher and a fire extinguishing system capable of discharging a fire extinguishing agent almost without waste and saving space.

The one fire extinguishing system includes the fire extinguisher 90 provided with a fire extinguishing agent storage container 10 having a cylindrical part 6 whose thickness is roughly uniform and a siphon tube 3 whose distal end part 5 gets close to or contacts the inner wall surface of the fire extinguishing agent storage container 10 by at least partially being flexible. The fire extinguishing agent storage container 10 is disposed so as to be inclined relative to a horizontal surface 20 within a limited space.