Experimental and numerical investigations have been carried out on the bead-carry-out phenomenon of electromagnetic bead chains in two component development process of electrophotography. Electrostatic pull-off characteristics of chains were measured in a magnetic field and then it was clarified how the critical electrostatic pull-off field to break chains and the amount of pulled-off carriers depended on the bead diameter and the magnetic field. Magnetic bonding force and electrostatic pull-off force were estimated numerically to evaluate these experimental results. It was deduced that the bead-carry-out phenomenon could be predicted qualitatively from the comparison of calculated magnetic and electrostatic force.