In this paper is described a 2D-numerical model of short-circuiting transfer process in GMAW. Time-dependent deformation and/or detachment of the molten drop at the tip of electrode wire were simulated with aids of the numerical solution technique based on finite-difference method, which was developed in order to investigate the effect of electromagnetic force and capillary force on the kinetics of metal transfer process. It is shown that the time required for breakup of liquid metal bridge, formed between the electrode and the weld pool, depends on the drop size before the contact and/or the short-circuiting current value.