Conventional drilling is a multipoint, end cutting tool that involves cutting of a hole into a solid. The present work entailed the use of Electric Discharge Machining (EDM)technique to produce micro-holes in two different materials using copper and brass electrode tubes. The workpiece materials were selected on the basis of their use in biomedical implants and aerospace engineering. Optimization of the factors and their levels were accomplished using L-16 orthogonal array by Taguchi method. It was observed that workpiece material S.S.-316L can be best machined with brass electrode-tube material at 3.0 ampere peak current and 75% duty factor. On the other hand, Ti-6Al-4V was found to be best machined with copper electrode-tube material at 3.0 ampere peak current and 50% duty factor.