The debris exclusion from the gap in EDM is an important phenomenon for stable and precise machining. Therefore, in this study, the dielectric fluid flow during electrode jump is experimentally observed, analyzed and computational calculated for die-sinking EDM. A dummy electrode-workpiece is fabricated to simulate the real dielectric flow in gap. Observation and flow visualization in the model gap is carried out by using PIV (Particle Image Velocimetry). Separately, the flow field in EDM gap is computed using CFD calculations. The results of both PIV analyses and CFD simulations are discussed and compared.