In organic chemistry, xylene or xylol (from Greek ξύλον (xylon) 'wood'; IUPAC name: dimethylbenzene) are any of three organic compounds with the formula (CH₃)₂C₆H₄. They are derived from the substitution of two hydrogen atoms with methyl groups in a benzene ring; which hydrogens are substituted determines which of three structural isomers results. It is a colorless, flammable, slightly greasy liquid of great industrial value.

The mixture is referred to as both xylene and, more precisely, xylenes. Mixed xylenes refers to a mixture of the xylenes plus ethylbenzene. The four compounds have identical empirical formulas C₈H₁₀. Typically the four compounds are produced together by various catalytic reforming and pyrolysis methods.