Peperomia pellucida (L.) Kunth has traditionally been used as a vegetable and herbal medicine in certain countries, though its safety remains uncertain. In this study, we investigated the plant’s ingredients, volatile compounds, antioxidative activities, and toxicity in Drosophila and mice. The results revealed that P. pellucida contains volatile substances that give it a unique flavor, making it suitable for consumption and rich in antioxidant compounds, such as polyphenols, tannins, flavonoids, saponins, alkaloids, and terpenoids. The total phenolic content (TPC) and total flavonoid content (TFC) of the plant extract were 273.33 ± 4.91 mg gallic acid equivalents/g extract and 199.8 ± 0.346 mg quercetin equivalents/g extract, respectively. The remarkable antioxidative properties of the plant extract were demonstrated by nearly doubling the lifespan of Drosophila against oxidative stress. Moreover, the extract did not cause any acute or chronic toxicity in mice after being fed the plant, as indicated by the normal blood parameters and the absence of hepatic shape damage or impaired function. In light of these findings, P. pellucida is deemed safe for consumption and its bioactive ingredients can be extracted to create functional foods and pharmaceuticals.