Experimental investigations were conducted on cutting of aluminium based composite material using Wire Electro Discharge Machining (WEDM). Objective was to optimize machining parameters of WEDM for high Material Removal Rate (MRR) and low surface roughness. Experiments were conducted using L9 orthogonal array, and the multi-objectives were normalized using Grey Relation Analysis (GRA). Process parameters considered were wire feed rate, Ton, Toff and sensitivity while process response considered was MRR and surface roughness. Composite material was processed through liquid metallurgy route using AA7075 as matrix material and particulates as Al2O 3(p) in 10% by weight. Multi-objective analysis indicated wire feed rate as the most contributing factor for surface roughness. Re-cast layer was identified under high magnification Scanning Electron Microscope (SEM) which revealed non-uniform flow of material over the surface. Wire used was analysed under SEM and indicated severe wear rate occurring along the length of wire characterised by pitting marks on the surface along with micro cracks and particulate adhesion. © 2017 Elsevier Ltd. All rights reserved.