Triphenylcarbethoxymethylenephosphorane is an organophosphorus compound with the chemical formula Ph<sub>3</sub>PCHCO<sub>2</sub>Et (Ph = phenyl, Et = ethyl). It is a white solid that is soluble in organic solvents.
The compound is a Wittig reagent. It is used to replace oxygen centres in ketones and aldehydes with CHCO<sub>2</sub>Et.