Plant-based fluoroprotein foam extinguishing agent is a novel fire suppressant developed by adding fluorocarbon surfactants and other components to the base of plant-based fluoroprotein foam. It is mixed with water in a ratio of 3:97 or 6:94 for use. This agent overcomes the shortcomings of conventional protein-based agents, such as poor fluidity, low resistance to oil contamination, slow fire suppression, inability to extinguish oil tank fires via sub-surface injection, and incompatibility with dry powder extinguishing agents. It is an environmentally friendly, green product free of malodorous substances like hydrogen sulfide and mercaptans.