The motion and deformation of a long elastic particle undergoing electrophoresis has been studied numerically and analytically The particle is elliptical in shape and is initially aligned with its major axis perpendicular to the direction of a uniformly applied electric field The particle tends to curl up at its ends and arches in the middle as it moves. The deformation of the particle is due to the viscous stress acting on the particle surface The results from the simulation are explained by evaluating the surface force distribution on a long thin object under similar conditions The pressure due to the inertia of the flow has a negligible effect on this deformation. (C) 2010 Elsevier Inc All rights reserved