Olive fruits (Olea europaea L) have several health and nutritional benefits dueto their high contents of antioxidant compounds. This study evaluated thehepato-renal toxic effects of pickled olive fruits that were treated with acidblack nigrosine dye (ABND) in mice. Twenty male Swiss albino mice (CD-1) were used to determine the median lethal dose (LD50) of ABND. Then otherforty male mice were equally divided into 4 groups (N = 10) as follows: Group1 (Gp1) was served as a control group. Gp2 was administered orally with anormal olive fruits extract (NOFE) as 150 mg/kg b.wt. Gp3 was administeredwith pickled olive fruits extract treated with KOH and ABND(POFE/B/KOH/ABND) as 150 mg/kg b.wt. The last group (Gp4) wasadministered with ABND alone as 60 mg/kg b.wt. The treatment of all theexperimental groups was daily for 2 consecutive months. At the end of theexperiment, percentages of body weight (% b.wt.) changes were calculated.Blood and sera samples were collected for determination the hematologicaland biochemical parameters Liver and kidney tissues were collected forhistopathological investigations. The results showed that the group of mice thatwere treated with POFE/B/KOH/ABND showed significant hepato-renaldysfunctions as evidenced by altering the some of hematological, biochemicaland histopathological parameters