This study is focused on fabrication and characterization of mixed matrix poly ether sulfone based nanofiltration membrane by phase inversion method. The effect of different amounts of Ilmenite (FeTiO3) particles as inorganic filler additive in the casting solution on physic-chemical characteristics of membranes was studied. Scanning electron microscopy, surface analysis, water content, contact angle, permeation, rejection and tensile strength measurements were carried out in membrane characterization. SEM images showed asymmetric structures with a dense top layer and porous sublayer for the membranes. Images revealed that membrane sub-layer porosity increased and top-layer thickness decreased by FeTiO3 utilizing in membrane matrix. SEM images showed smooth surface for modified membranes compared to pristine one. Membrane water content improved initially by increase of additive concentration up to 0.05 wt% into the casting solution and then decreased. The contact angle measurements showed that membrane surface hydrophilicity improved using Ilmenite in the membrane matrix. The membrane tensile strength improved initially by increasing additive concentration into the casting solution and then decreased. Utilizing of Ilmenite into the membrane matrix caused increase of water flux and salt rejection from 10 to 172.4 L/m2·h and 53.9 to 88.5%, respectively.