NEW MATERIAL:3-Nitrophenylmalonidaldehyde of formula I. USE:A material suitable for various devices such as optoelectric devices, second higher harmonic wave generation devices, piezoelectric devices, waveguides and semiconductors, especially used in optoelectronic fields such as optical information treatments, optical communication, etc., using oriented or collected films or layers as constituting elements thereof. PREPARATION:A compound of formula 2 is reacted with an excess amount of oxyphosphorus chloride and dimethylformamide at approximately 20-80 deg.C and subsequently treated with sodium hydroxide to prepare a compound of formula 3, which is reacted with the sodium hydroxide at approximately 20-100 deg.C and subsequently treated with hydrochloric acid to provide the compound of formula I.