To eliminate an adverse influence on the human body and metals by incorporating potassium bicarbonate, potassium chloride, 1-2-3 benzotriazole, sodium molybdate, ethylene glycol, urea, phosphoric acid and fluorine surfactant into a fire extinguishing agent compsn.

The potassium bicarbonate and potassium chloride which exhibit a fire extinguishing effect by forming a gelatinous reactant to a frying oil fire and the fluorine surfactant which exhibits fire extinguishing performance by forming a frothy material to the surface of the frying oil fire are incorporated into the fire extinguishing agent compsn. Further, the 1-2-3 benzotriazole and sodium molybdate having a rust preventive effect and an effect of improving soln. stability and the urea and ethylene glycol as a soln. stability improving agent and the phosphoric acid to stabilize the soln. by making its pH neutral are incorporated therein. As a result, the fire extinguishing agent compsn. is made to exhibit the excellent fire extinguishing effect to various fires including the frying oil fire and is made to have the lower corrosiveness to the metals.