Background and Aim: Pulp diseases are extremely disturbing and common finding in pediatric patients. It is highly advisable to address/manage these conditions at earliest so as to avoid any possible future complications. This in vivo study was conducted to assess the clinical success rates of mineral trioxide aggregate and formocresol in pulpal treatments of primary teeth. Materials& Methods: Mineral trioxide aggregate and formocresol was assessed clinically for their performances and outcomes. Total 30 pediatric patients were included in the study. One deciduous molar (with involved pulp) per patient considered. Pulpal therapy was initiated carefully after removal of soft caries and tooth portion. Group 1 has 15 primary molars treated with formocresol while Group 2 has 15 primary molars treated with mineral trioxide aggregate. Patients were reevaluated in their post-operative phases for clinical outcomes and performances. The treatment intervention was declared successful of failed. Patients were checked at prefixed post-operative period of 2, 4, 6, 8, 10 months. Results were put in spread sheet and subjected to basic statistical analysis. P value less than 0.05 was taken as significant (p<0.05). Statistical Analysis and Results: Statistical analysis was completed by using statistical software Statistical Package for the Social Sciences. All patients were in the age range of 6 to 9 years. In the age group of 6 years, there were 5 male and 3 female patients. P value was highly significant for that (0.01). For Group 1, P value was highly significant at the timings of 4, 6, 10 months. There was an increasing pattern of success of formocresol therapy was noted with increasing post-operative timings. For Group 2, P value was highly significant at the timings of 2, 4, 8 months. Maximum 13 out of 15 patients/primary tooth showed successful pulp treatment in 10 months post-operative time. Evaluation amongst all studied Groups was completed using one-way ANOVA which gave highly significant results. Conclusion: Authors concluded that formocresol and MTA both have clinically satisfactory results however, the Mineral Trioxide Aggregate exhibited higher success rates than formocresol. Nevertheless, the implications of this study must be correlated clinically while judging overall success rate. Authors also presume some long term future studies to be executed to validate and confirm our results. Key Words: Formocresol,Mineral Trioxide Aggregate, Pediatric, Primary Teeth, Pulp Therapy, Pain, Analgesia.