Machinability of aerospace material, Inconel 625 through Wire cut electrical discharge machining has been performed and compared using Taguchi’s Orthogonal L18 (21*35). Normal diffused and cryogenic treated diffused wires are being used as a tool electrode to investigate the effects of machining parameters viz. tool electrode, peak current, pulse on time, pulse off time, wire feed and wire tension on the response MRR. The present study resulted that cryogenic treated tool electrode give better performance in comparison to normal wire electrode assisting in improving stock removal and less electrode wear. Pulse on time and peak current are observed as the most influenced parameter. Scanning Electron Microscopy (SEM) studies has been conducted and presented.