Abstract: The present invention relates to 2-substituted cephem compounds of Formula (I) having a quaternary ammonium group on the 3-side chain, preferably together with a cathechol group, or pharmaceutically acceptable salts thereof, which exhibit potent antimicrobial spectrum against a variety of bacteria including Gram negative bacteria and/or Gram positive bacteria, corresponding pharmaceutical compositions, methods of making, treatment methods for bacterial infections or uses thereof.