The product is colorless transparent liquid, can't exist in pure state, only exist in aqueous solution. It is stable in concentrated solution, will decompose when heated to 130°C and can mutually soluble with water or alcohol. It can slowly decompose to produce hydroxyl fluoboric acid(HBF3OH) in aqueous solution. Its stability gradually reduces when contacting with glass surface, the hydrolysis degree of 0.047M solution of fluoboric acid reaches to 72.6% from original 20.6% after stored in glass window for 32 days. It has strong corrosion, but doesn't corrode glass under normal temperature. It can react with metal, metal fluoride, oxide, hydroxide or carbonate to produce corresponding fluoboric salt, toxic.