Bupivacaine exists as a mixture of two enantiomers, levobupivacaine and dexbupivacaine. Data suggests that levobupivacaine has equal local anesthetic potency, with reduced potential for central nervous system and cardiovascular toxicity. This study compares the clinical efficacy of 0.5% isobaric levobupivacaine with 0.5% isobaric bupivacaine for spinalanesthesia in lower abdominal surgery. The efficacy endpoint measures included sensory onset and duration, motor block duration, hemodynamic & respiratory variables, postoperative analgesia and adverse effects of the drugs. The results of this study demonstrated that the sensory onset was significantly shorter and the sensory duration was significantly longer with levobupivacaine. The motor duration was similar in levobupivacaine and bupivacaine groups. No significant differences between the groups as regards the mean arterial blood pressure and heart rate. No significant differences as regard respiratory rate and oxygen saturation. Postoperativeanalgesia was longer with levobupivacaine and no adverse effects related to the drugs of, significant importance, were reported a part from postoperative headache and backache.