Isomorphous substitution of heteroatoms is an effective platform for finely tuning the pore chemistry, pore structure, and surface properties of the zeolite framework as catalysts or separation membranes. A continuous and compact isomorphously substituted tungsten (W)-MFI membrane was firstly developed on coarse α-Al 2 O 3 tubes dip-coated with W-MFI seeds using hydrothermal secondary growth using pretreated synthesis solution. The synthesized W-MFI membrane is found to be ethanol permselective having a pervaporation based separation factor and flux of 69 and 2.50 kg/m 2 .h, respectively while exhibiting the highest separation index of 170 kg/m 2 .h for the separation of 5 wt. % ethanol-water mixture among the reported tubular MFI membranes. The isomorphous substitution of W improves the hydrophobicity and also plays a significant role for the enhanced separation performance.