This study provided a first report on a facile strategy to fabricate superhydrophilic and low-fouling multilayer coatings on polyvinylidene fluoride (PVDF) membrane by layer-by-layer (LBL) assembly of Fe3+ and phytic acid (PA) alternately. Successful modification was verified by scanning electron microscope (SEM) observation and element analysis. It was found that, the resulted PA/Fe@PVDF-OH membrane with five bilayers' (BLs') modification performed the optimal antifouling properties under conditions in this study. As compared to the original PVDF-OH membrane, the coated membrane surface possessed super hydrophilicity (water contact angle was 11.34 degrees) and improved negative charge density. Thermodynamic analysis showed that, the changes of interaction energy caused by both of the modified surface thermodynamic properties and morphology were responsible for the improved antifouling performance of the coated membrane. The facile coating strategy, together with the method assessing interaction energy in this study provided a potential solution to optimize LBL assembly technique and to quantitatively tune antifouling ability of membranes.