This study tended to modify polyvinylidene fluoride (PVDF) microfiltration membranes by the addition of nanomagnesium oxide (nano-MgO) particles via fabrication of the phase inversion method. The detailed structure and properties of these composite membranes were characterized. The findings showed that the membrane hydrophilicity was significantly improved with the addition of nano-MgO content increasing from 0% to 1%. The improved hydrophilicity and decrease in roughness of the composite membrane enhanced the antifouling performance during the reclaimed water treatment.