BACKGROUND:Labor pain is one of the most intense pain that a woman experiences .Labor epidural analgesia provides efficient pain management, improved parturient satisfaction, and the ability to administer anaesthesia as necessary. AIM:This study was conducted to compare the efficacy of Magnesium sulphate and Fentanyl as adjuncts to Ropivacaine in labor epidural analgesia. MATERIALS &METHODS: After the approval from the institutional ethics committee and CTRI registration,60 primiparturients of ASA-2, in active labor, requesting labor analgesia were randomised into two groups of 30 each : Group M (received 0.125% Ropivacaine + 5 mg/ml Magnesium Sulphate + Normal saline a total volume of 10 ml) and Group F( received 0.125% Ropivacaine + 2mcg/ml Fentanyl + Normal saline a total volume of 10 ml).Pain was assessed using Visual Analogue Scale (VAS). Time of onset and duration of analgesia of bolus dose were noted. RESULTS: Onset of analgesia was significantly faster in group M (4.03±0.99 min) as compared to group F(6.36±1.09 min), P < 0.0001. Duration of analgesia after initial bolus dose was also significantly longer in group M (90.83 ± 42.19 min) than in group F (69.5 ± 8.7 min), P = 0.0088. Mean VAS scores were significantly less in group M than in group F .