Excess molar volumes (V-m(E)) of binary mixtures of 2-methyl-3-buten-2-ol [CH3C(OH)(CH3)CHCH2] with four 1-alcohols: methanol, ethanol, 1-propanol and 1-butanol at 298.15 K and atmospheric pressure are derived from density measurements with a vibrating-tube densimeter. All the excess volumes are negative in the systems over the entire composition range. The results are correlated with the Redlich-Kister equation. The effects of chain length of 1-alcohols on V-m(E) are discussed. The apparent molar volumes of 2-methyl-3-buten-2-ol and 1-alcohols are calculated respectively.