The surface properties of polymer membranes are very important to their separation performance. It is generally accepted that a hydrophilic membrane surface is favorable for applications in water treatment and bioseparation, because the hydrophilic surface can enhance water permeate flux and mitigate membrane fouling. Microporous polypropylene membrane (MPPM) is a promising membrane material for membrane distillation and membrane gas-liquid contactor, due to the intrinsically high hydrophobicity of polypropylene. However, it is the hydrophobicity that severely limits the wider application of MPPM in aqueous solutions and biomedical fields. Surface hydrophilization is, therefore, logically necessary. Surface engineering of polymer membranes encompasses those processes which modify the membrane surfaces to confer different properties to those of the bulk and thus improve their in-service performance. This review provides a concise summary and discussion of the surface engineering strategies developed in our laboratory and reported in scientific literature, which aim at enhancing the surface hydrophilicity and antifouling property of MPPM. (C) Koninklijke Brill NV, Leiden, 2011