A set of 17 novel ketolides bearing an aryltetrazolyl-substituted alkyl side chain were synthesized and evaluated for their antibacterial activities, which the aryltetrazolyl group was selected to replace the hetero-aryl moiety of the side chain in telithromycin for designing new compounds. The synthesis of aryltetrazolyl alkylamines was reported in detail. The antibacterial activities of new ketolides were evaluated against a number of pathogens including macrolide-resistant organisms by using telithromycin as the reference. Many of the evaluated compounds exhibited remarkable activities against both erythromycin-susceptible and erythromycin-resistant organisms such as Staphylococcus aureus (except S. aureus AD-08), Pseudomonas aeruginosa and Escherichia coli. Among these, the compound 11e exhibited excellent antibacterial potency against all the strains in comparison with others.