Piper sarmentosum Roxb. is a edible as well as a traditional medicinal plant in South East Asian countries. Objectives: The current study aimed to test antioxidant and antimutagenic activities of the P. sarmentosum extracts. Methods: The dry leaves of this plant were extracted by the maceration method using petroleum ether, hexane, dichloromethane, ethyl acetate and methanol as the solvents. The antioxidant activity was performed using the DPPH (2,2-diphenyl-1-picrylhydrazyl) and the FRAP (ferric reducing antioxidant power)assays. The mutagenic and antimutagenic were tested using the Ames test in Samonella typhimurium TA98 and TA100 strains. Result and conclusion: The hexane and the methanol extracts possessed the highest antioxidant activities in the DPPH and the FRAP assay with the EC50 value of 29.63 ± 0.56 µg/mL and Fe II equivalent of 0.56 ± 0.12 µmole/mg of the extract, respectively. In the Ames test, the leaves extract were no mutagenic activity, the dichloromethane extract exhibited the strongest antimutagenic activity both in TA98 and TA100 strains. From this in vitro study, It can be concluded that the P. sarmentosum extracts have excellent potential to further study as supplementary products for tonic and human cancer prevention products