High surface area magnesium oxide (∼250–300m2g−1) was synthesized via the thermal decomposition of different precursors including (MgCO3)4Mg(OH)2, Mg(OH)2, MgCO3 and MgC2O4. The high surface area MgO displayed exceptionally high catalytic activity for the liquid phase Meerwein–Ponndorf–Verley (MPV) reaction of benzaldehyde with different alcohols. The effect of the calcination temperature and precursor source on the catalytic activity and morphology of MgO has been investigated in detail. It was found that the optimum calcination temperature was 450°C leading to a high surface area material containing no MgCO3 which is the key to obtaining high catalytic activity of MgO for the MPV reaction. The high area MgO catalyst could be reused without loss of catalyst activity. The simplicity of the synthesis method gives this methodology widespread applicability in countless applications that currently use homogeneous base catalysts or stoichiometric bases as reagents.