Aim: The present study explored the therapeutic in detail antioxidants and effect of aqueous Terminalia arjuna (TA) bark extract against acetaminophen (APAP) induced hepatotoxicity through studies on serum marker enzymes, phosphatidylinositol3kinase/protein kinase B (PI3K/AKT) pathway, CYP2E1 evaluations. Biochemical, antioxidant, cytochrome P450 2E1 (CYP2E1) enzyme, and PI3K/AKT cell signal enzymes were observed with the appropriate methods of study. Materials and Methods: The animals were divided into five groups (each having six animals): control group, Acetaminophen (APAP) toxic group, N-acetylcysteine (NAC) group, TA 250 mg/kg group, and TA 500 mg/kg group. APAP toxic dose of 750 mg/kg body weight was administered along with 0.5% of hydroxypropyl cellulose (vehicle) 24 h before sacrificing the animal. Results: The biochemical, antioxidant, Histopathological, CYP2E1 enzyme, PI3K, AKT protein expression analysis were shown increased antioxidant level, increased PI3K/AKT level, decreased liver function marker level and decreased CYP2E1 level in TA500 mg group compared with APAP toxic group (P < 0.01). The findings suggest that TA (500mg/kg) drug reduced Acetaminophen toxicity via antioxidant and molecular mechanisms. Conclusion: The present study concluded that TA 500 mg/kg high dose is more effective to restore the liver tissue through APAPinduced hepatotoxicity in Wistar albino rats.