Methanol-D4 (Cas Number 811-98-3), also known as Tetradeuteromethanol, is a deuterated solvent analog of methyl alcohol in which all four hydrogen atoms are replaced by deuterium. It is commonly used in NMR Spectroscopy.

Methanol-d4 may have been used as solvent in the nuclear magnetic resonance spectrum analysis for characterizing phenolic compounds separated from olive oil using high performance liquid chromatography and vanillic acid and 4-hydroxy-3-methoxystyrene formed via biotransformation of Rhodotorula rubra.