Abstract:Antibiotic susceptibility testings were made by gradient diffusion (E Test; AB Biodisk) on deMan, Rogosa, Sharpe (MRS) agar plate for 12 strains of probiotics commonly used as an ingredient of functional foods. The antibiotics included, Amoxicillin/clavulanic acid, Vancomycin, Trimethoprin/sulfamethoxazone, Trimethoprin, Gentamicin, Chloramphenicol, Streptomyxin, Tetracycline, Amikacin, Kanamycin, Nalidixic acid, Ceftriaxone, and Cephalothin. The result showed that all strains were resistant to Amikacin and Kanamycin, and sensitive to Amoxicillin/clavulanic acid and Chloramphenicol. The main resistant pattern in antibiotic susceptibility testing was Amikacin(12/12), Kanamycin(12/12), Nalidixic acid (11/12), Trimethoprin/sulfamethoxazone (10/12), Trimethoprin(9/12)and Vancomycine(7/12).