Micro drilling process plays a vital role in modern high end applications in the field of aerospace, nuclear and micro mould making industries. Conventional micro drilling poses challenges not only type of tools but also its precise rotation for an improved hole geometry. Micro EDM process is capable of meeting current industrial requirements. In this paper, an attempt is made to investigate the influence of the characteristics of Inconel 718 on electric discharge drilling process for 0.5 mm diameter micro hole with tubular brass electrode of same size. Experiments were conducted using demineralized water as dielectric medium by varying current, pulse-on time and pulse-off time in three levels while keeping electrode diameter, spindle speed, feed rate and material thickness constant. Taguchi analysis was performed on L9 orthogonal array experimental results show that the effects of input parameters are having varying contributions on output parameters material removal rate, hole taper and its change in hole size called diameter over cut during process © 2019 Elsevier Ltd.