AbstractBackground: Baricity is the density of a substance compared to the density of human cerebrospinal fluid which used in anaesthesia to determine the manner in which a particular drug will spread in the intrathecal space and produce shorter duration of onset, greater level of blockade and fast recovery. Aim: To compare the clinical efficacy of hyperbaric Ropivacaine and Bupivacaine under spinal anaesthesia in terms of duration of onset, blockade and recovery. Settings and Design: Prospective, comparative and randomized double blind study. Methods and Material: About 80 patients from K S Hedge Medical College Hospital, NITTE University, Mangaluru, Karnataka, India were enrolled between January 2015 to August 2016 by random sampling method and divided into two groups as A and B. Group A received 3ml of 0.5% hyperbaric Bupivacaine and Group B received 3ml of 0.5% hyperbaric Ropivacaine. Subarachnoid block in L3-L4 space was performed by considering following parameters such as Onset and duration of block and recovery following injection. Statistical Analysis: Unpaired t test and Chi square test. P<0.05 was considered as statistically significant. Results: The duration of onset of sensory block to T10 with 0.5% hyperbaric Bupivacaine was 5.9±0.955 min when compared to 0.5% hyperbaric Ropivacaine which was 5.50±1.219 min with p value of 0.107. Conclusions: Hyperbaric Ropivacaine has showed more favourable profile than hyperbaric Bupivacaine in terms of shorter duration of onset, with higher level of sensory blockade and faster recovery.