This study was aimed to investigate effect of L-carnitine (LCAR) on adverse effect of doxorubicin (DOX) on heart tissues. For this purpose, a total of 21 healthy albino New-Zealand rabbits were divided into 3 groups. Rabbits in group I (n=8) received DOX at a dose rate of 0.6 mg/kg/day body weight (BW) intra peritoneally (IP) for 6 days, group II (n=7) received DOX at a dose rate of 0.6 mg/kg/day BW, IP and LCAR at dose of 1000 mg/kg/day BW IP for 6 days and group III /n=6) received LCAR at dose of 1000 mg/kg/day BW IP for 6 days. Blood samples from auricular vein were taken from all animals at the beginning of the experiment (before drug administration) and 2 hours after drug administration daily for 6 days. Pathological examination of all animals was carried out at the end of the study. Macroscopic and microscopic alterations were noticed only in heart of the DOX-group rabbits. Cardiac troponin-I and T rapid assay tests of animals in all groups were negative throughout the study. There were no statistically significant changes in biochemical parameters on day 0 between the groups, while on subsequent days these parameters altered. Blood concentrations of troponin-I, CK-MB and LDH were significantly higher in DOX received group when compared to the groups given LCAR. The results of histopathological and biochemical analysis reveal that parenteral LCAR administration had a protective effect against adverse effect of DOX on heart and kidney.