A cephalosporin derivative represented by the formula ##STR1## wherein R.sup.1 is a hydrogen atom or a protecting group of the amino group, R.sup.2 is a hydrogen atom or a protecting group of the hydroxyl group, R.sup.3 is a hydrogen atom or a protecting group of the carboxyl group, X is a halogen atom, a cyano group, a vinyl group, a lower alkoxy group having 1 to 4 carbon atoms or a lower alkylthio group having 1 to 4 carbon atoms and n is an integer of 1 to 3, and a non-toxic salt thereof are useful as antibacterial agents for oral administration.