B Banana (Musa Paradisiaca) is plant that is easy and commonly found in Indonesia. Besides the fruit that delicious to be consumed, it also could be processed to other various ways such as fried and any other else. Despitefully, banana itself result a waste from its peel that is countless. Banana’s peel been studied has content of flavonoid, alkaloid, and tannin that is a compound of antibacterial. Streptococcus mutans is one of the bacteria that cause of dental caries and can be found in the mouth cavity. This aims of study is to understand the effect of antibacterial comparison extract the peel Musa paradisiaca on the growth of S. mutans bacteria using concentrated 5%, 10% and 15% fraction ethanol and ethyl acetate, chlorhexidine 0,2%, tetracycline 2% and aquadest as control. The extract have been tested its inhibition zone with diffusion method on a medium of blood agar and get incubation period for 24-48 hours. The results of inhibit zone in 24 hours of ethanol extracts concentrated 5%, 10%, 15% is 27,78 mm , 32,73 mm , and 33,22 mm. While fraction ethyl acetate shown 30,85 mm, 33,38 mm, and 33,29 mm. In 48 hours inhibition zone of the ethanol extract become 27,81 mm, 32,76 mm, 33,24 mm and ethyl acetate become 30,89 mm, 33,41 mm, 33,32 mm. From both fractions, are shown the best diameter of an inhibition zone of ethyl acetate 10%, which proved through statistical testing using one-way ANOVA (p<0.05), that means there is significant effect between ingredients in M. paradisiaca’s peel towards S. mutans bacteria. It is concluded both extract potential to inhibit the growth of S. mutans bacteria. It’s hoped that the research on banana peel extract can be used as a substitute for usage of a mouthwash.