Background:-To evaluate and compare Pulpal Response to Tri-antibiotic Paste and Allium Sativum with Formacresol as Pulpotomy Medication in Primary Teeth. Materials and Methods:-30 children in age group 7-9 years have bilateral primary teeth indicated for orthodontic serial extraction .children divided into two groups, (group I) included(15) children had bilateral primary teeth, the right side tooth treated with tri-antibiotic past (3 mix) (group IA) and left side tooth treated by formacresol (group IB) and (group II) included (15) children had bilateral primary teeth, the right side tooth treated with allium sativum oil (A. sativum) (group IIA) and left side tooth treated by formacresol (group IIB) . Each tooth was treated with standard pulpotomy procedure. . Patients were recalled after 15 and 30 days’ time interval as a part of orthodontic treatment. Teeth in each group were extracted and were subjected to decalcification procedure for histopathological evaluation. Results:- In group(I A) Nearly normal pulpal architecture was observed. Another finding common to all experimental groups was the presence of inflammatory processes of different levels of severity. Moderate amount of inflammatory cell infiltration was noted about 50-60% in cases after 15 and 30 days. In addition the results of group (IB), (IIB) there was pulpal inflammation was prominently observed in all cases treated with formacresol. After 15 days about 33.3% of cases showed severe inflammation with lymphocytes and foamy macrophages while 66.6% showed moderate inflammatory infiltration. By the end of 14 days cases with severe pulpal inflammation were about 46.6%. Also, in group (IIA) there was pulpal inflammation was prominently observed in all cases treated with formacresol. After 15 days about 33.3% of cases showed severe inflammation with lymphocytes and foamy macrophages while 66.6% showed moderate inflammatory infiltration. By the end of 30 days cases with severe pulpal inflammation were about 46.6%.Conclusion:- 1-Odontoblast remained vital in most cases treated with Both Tri-antibiotic paste and A. sativum . 2-Interal root resorption found in most specimens treated with formacresol .Recommendations: Further clinical studies with long time evaluation periods should be done to investigate the effects of the three medicament on pulp tissues of primary teeth .