Introduction: Pulpotomy therapy is a treatment commonly carried out in pediatric patients to counteract the infection present, frequently chemical agents are used as antimicrobials being somewhat contradictory in terms of their effects. Objective: To evaluate the antimicrobial action of 10% ethanolic extract of propolis in pulp therapy of primary dental organs. Materials and Methods: In this study, 10% ethanolic extracto of propolis (EEP) of natural origin was used for the treatment of pulpotomies.Its antimicrobial action was evaluated by collecting microbiological simples before the placement of EEP sample (S1) and after its placement sample (S2). The degree of microbial development was evaluated in McFarland Units and by CFU count at two initial times and24 hrs. Results: Propolis showed antimicrobial capacity since the results show an average decrease in bacterial growth amog the 20 samples, being from 8.30 to 8.10 in S1 and S2 as well as from 9,18 to 8.96 in S1a ande S2a. The results show an antimicrobial effect, obtaining differences between S1 and S2, results that favor the antimicrobial capacity of propolis. Conclusions: The use of plant extracts or natural derivatives such as propolis for the treatment of pulp therapy such as propolis for the treatment of pulp therapy such as pulpotomies in primary teeth is promising as an alternative to formocresol.