Objective: To compare the outcome of pulpotomy of immature permanent teeth using calcium hydroxide (CH) and mineral trioxide aggregate (MTA) as sealing materials. Methods: This randomized controlled trial was carried out in the Department of Pediatric Dentistry, Punjab Dental Hospital, Lahore. Duration of the study was 9 months: 6 months data collection (February 01, 2016 to May 31, 2016, and August 01, 2016 to September 09, 2016) and 3 months follow up period (October 01, 2016 to December 31, 2016). Total of 110 patients was included in this study. They were divided into 2 groups; A and B, each comprising of 55 patients. All cases were treated by the same operative team. Conventional access cavity was formed and coronal pulp was removed to the cervical level using a sharp spoon excavator and a sterile round diamond bur. Results: There were 25 males (45.4%) and 30 females (54.6%) in calcium hydroxide group, while in the mineral trioxide aggregate group, there were 26 males (47.2%) and 29 females (52.8%) with a male to female ratios 1:1.2 and 1:1.1 respectively. The mean ± SD ages were 8.93 ± 1.82 and 8.89 ± 1.97 years. Total 44 patients (80%) have success and 11 patients (20%) have a failure in calcium hydroxide group, while in mineral trioxide aggregate group, 48 patients (87.2%) have success and 7 patients (12.8%) have a failure. Statistically, there was no significant difference (p>0.05) between the two groups. Conclusion: Mineral trioxide aggregate showed good clinical and radiographic success as a pulpotomy agent in immature permanent teeth and seems to be a suitable alternative to calcium hydroxide.