The objective of this research was to determine antibacterial activity toward Streptococcus mutans and antioxidant. Non-Factorial Randomized Block Design method was used in this study. The first stage used nonfactorial randomized block design which consisted of three blocks and six treatments as follows: F1 (8 g betel leaf, 2 g betel lime), F2 (8 g betel leaf, 2 g betel lime, 2 g areca nut, 1 g gambier), F3 (8 g betel leaf, 2 g betel lime, 2.5 g areca nut, 1.5 g gambier), F4 (8 g betel leaf, 2 g betel lime, 3 g areca nut, 2 g gambier), F5 (8 g betel leaf, 2 g betel lime , 3.5 g areca nut, 2.5 g gambier) and F6 (cefadroxil).The observed parameters in betel chew formulation were antibacterial activity, cellulair metabolites leakage and antioxidant. Results of chemical and microbiological analyses showed that the best treatment was found on F5 treatment (8 g betel leaf, 2 g betel lime, 3.5 g areca nut, 2.5 g gambier) antibacterial activity of 8.25 mm, with antioxidant IC50 of 2.77 mg/ml and cellulair metabolites leakage of 1.22 nm (at wave length of 260 nm) and 1.51 nm (at wave length of 280 nm), respectively.