The electrophoretic mobility of a particle coated with an ion-penetrable charged membrane in a uniform electric field is investigated. In particular, the effects of the distribution of fixed charges and that of the dielectric constant in the membrane phase on the electrophoretic mobility are investigated. The results of numerical simulation reveal that these effects can be significant. In particular, for a constant total amount of fixed charges, assuming a homogeneous fixed charge distribution may lead to an appreciable deviation.