Triethyl phosphite is an organic compound with the chemical formula of C6H15O3P. It is a colorless transparent liquid, insoluble in water, and easily soluble in organic solvents such as ethanol and ether. It will hydrolyze to diethyl Phosphorous acid in water for a long time. It can be used as a plasticizer, lubricant additive, and stabilizer, as well as an intermediate for pesticide insecticides such as "Futianong" and "Fenfencarb", and as a raw material for the pharmaceutical analgesic agent phenthiazide.