Background and Objectives: com­bined spinal epkjural anaesthesia is a suitable anaesthetic technique for pel­vic surgery. The effects of baricity of spinal local anaesthetics have been studied during spinal anaesthesia. Yet, there is a need to study these ef­fects during combined spinal epidural anaesthesia. We aimed to compare block characteristics, haemodynam-ics, analgesia and side effects of epi­dural/ hyperbaric bupivacaine-tentanyl spinal anaesthesia and epidural/ plain bupivacaine- fentanyl spinal anaes­thesia. Methods: 50 patients subjected to pelvic urokigic procedures were ran­domly allocated to receive either spi­nal hyperbaric bupivacaine- fentanyl  (n=25) or spinal plain bupivacaine-fentanyl (n=25). Both groups received epidural bupivacaine 0.25% via epidu­ral catheter at upper interspace. Heart rate, mean arterial blood pressure, motor block score, sensory level/ re­gression, drug supplementation and side effects were recorded. Results : the plain bupivacaine group snowed delayed regression of sensory block in 4 (16%) of patients. Patients in the plain group needed more vasoacative drugs than the hy­perbaric group (36% and 12% respec­tively). Otherwise, there were no strik­ing differences in haemodynamics, block characteristics or the side ef­fects between plain and hyperbaric groups. Both techniques produced comparable analgesia.