"Tocosh" is a potato that has undergone a process of hydraulic oxidation that enhances its antimicrobial properties so that this natural resource can be used in medical sciences. The aim of this study was to develop and evaluate the antibacterial and cytotoxic activity of a new experimental tooth based on "Tocosh" on the cell lines 3T3 and DU145.To evaluate the cytotoxicity, cell cultures 3T3 and DU145 were used. Cell viability was determined by the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) in a medium containing 10% calf serum where the cells were preincubated at a concentration of 1 × 10 cells/mL in culture medium for 3 hours at 37°C and 6.5% CO. Then, the absorbance was measured using a microplate reader where the formazan crystals were diluted with acidic and cold isopropanol, and quantified in an ELISA reader. To evaluate the antibacterial effect, the Kirby Bauer inhibition halos method was used on strains of (ATCC 25923), (ATCC 25175), and (ATCC 49456). (tocosh) was not cytotoxic because it only had one CC at the concentration of 0.26927 mg/mL and 0.26845 mg/mL for the cell lines 3T3 and DU145, respectively. Tocosh toothpaste (TD) has an antibacterial effect against and .The new ecological dentifrice was not cytotoxic since it did not alter cell viability because its CC was only 0.268 and 0.269 μg/mL for the 3T3 and DU145 cell lines, respectively; however, it presented an optimal antimicrobial activity against the oral strains evaluated.This research has great potential for clinical use because this new dentifrice has antimicrobial activity against different oral germs. How to cite this article: Mayta-Tovalino F, Sedano-Balbin G, Romero-Tapia P, Development of New Experimental Dentifrice of Peruvian (Tocosh) Fermented by Water Stress: Antibacterial and Cytotoxic Activity. J Contemp Dent Pract 2019;20(10):1206-1211.