Abstract: Gentamycin and Amikacin are 2 of the most important antibiotics of Amynoglycosides family. They are most effective on gram-negative bacteria but one problem limiting their usages is their nephrotoxic effects on kidneys. Regarding to the proved higher wide-spread bactriocidal activity of Amikacin than Gentamycin, researchers were about to compare their nephrotoxocity level so that if Amikacin's lower nephrotoxicity effect can be proved, it will be the choice antibiotic between these two. About 48 rabbits were divided in 3 groups based on time (days 3, 7 and 14). In every group, 6 rabbits were injected by Gentamycin, 6 rabbits were injected by Amikacin and 4 as control group. Injections were done once in a day. About 24 h after the last injection, the rabbits were sacrificed and histopatholgic slides were provided from their kidneys. The slides were examined on the necrosis severity based on some measures (mentioned in the full text). The results after being statistically analyzed (p<0.05) showed a remarkable and significant difference between 2 groups so that the Amikacin-induced necrosis was dramatically less than Gentamycin-induced necrosis. So because of Amikacin’s higher bacteriocidal effect and less nephrotoxic damage, it can be recommended as a choice drug between these 2 considered antibiotics.