The skin of the pineapple (Ananas comosus) contains the enzyme bromelin, tannins, and flavonoids which have antibacterial effects against the growth of Streptococcus mutans causes dental caries. This research aims to get formulations of toothpaste extract of pineapple skin and knowing the effectiveness of antibacterial toothpaste extract of pineapple skin against the growth of Streptococcus mutans. This research uses the extracted pineapple skin using the method of maceration with solvent ethanol 90%. Formulation of the toothpaste was done using CaCO3, sorbitol, gum Arabic, papermint oil, aquades, and Glycerin. Do test the quality of the toothpaste include organoleptic, its homogeneity, and a pH. Toothpaste extract of pineapple skin concentration 6.25%, 12.5%, 25%, and toothpaste without extracts, and pepsodent toothpaste® in test method using diffusion on TSA medium. Antibacterial toothpaste power against the growth of Streptococcus mutans evaluated diameter Power Zone Inhibition. Evaluation of data quality of the formulation of the toothpaste and test the effectiveness of antibacterial toothpaste extract skin the pineapple (Ananas comosus) analyzed are descriptive. Test evaluation of toothpaste formulations for organoleptic extract toothpaste texture on the skin of a pineapple concentration of 25% less soft compared to other concentrations, its homogeneity test at concentrations of 25% is also less homogeneous, and pH test results are 5-6. on the Diameter of the Inhibition Zones toothpaste extract skin the pineapple (Ananas comosus) concentration of 6.25%, 12.5%, 25%, and toothpaste without the extract is 0 mm and pepsodent toothpaste ® is 19 mm. Formulations of toothpaste extract of the best pineapple skin at concentrations of 12.5% and DZI toothpaste extract of pineapple skin concentration 6.25%, 12.5%, and 25% not efektiv as Streptococcus mutans antibacterial power.