This study was designed to examine the effect of different dose of Pentostam administration in male albino mice as a model, todetermine their effect on some biochemical and heamatological parameters. 28 adult male of BALB/c wild mice aged 8- 12 weeks andweighing 25-39 gm were used and i.p. injected with 10mg/kg, 20mg/kg, and 40mg/kg pentostam in addition to a control group. After28 therapeutic days, blood sample were collected from each animal. The result of Biochemical Index of the serum obtained showedthat there were increase significant differences between different concentration doses on AST, ALT, ALP, Urea, Creatinine and BUNas compare to control group at (p >0.01). Conversely in case of Albumin and Total protein were the result showed decrease significantdifference between different concentration doses on this parameter as compare to control group of the same at (p> 0.01). while nosignificant differences between the different concentrations group of doses on Total bilirubin, where the F value was (1.00). The resultof Hematological Index of blood sample showed that there were decrease significant difference at (P ≤ 0.01-0.05) in hemoglobin, HCT,WBCs, LYM and MON concentration in the different concentrations dose of treatment as compared to control group. Conversely, forMCHC, NEU and EOS there were increase significant difference at (P ≤ 0.05-0.01) as compared to the control group. While nosignificant changes (P ≤ 0.0-01.05) in the parameters of RBCs, MCV, MCH, BAS count and Platelet were found when compared withcontrol animals. Biochemical and hematological evaluation pattern still an important role to evaluate drug toxicity. However, theresults of this study concluded that, different doses of Pentostam can cause hepatotoxicity and nephrotoxicity. Therefore, it will beimportant of change in anti-leishmanial regimen to reduce their side effect