Breast cancer is one of the diseases that has the highest mortality rate in Indonesia and most suffered by women. Cancer treatment with chemotherapy agents causes many side effects so that it can reduce the patient's quality of life. For this reason, it is necessary to look for antioxidant agents that are relatively safe and have minimal side effects, including natural ingredients. One of the plants that can be developed as an antioxidant agent is tea leaves (Camellia sinensis) and orange peel (Citrus reticulata) which are proven to inhibit cancer cell proliferation. This study aimed to determine the antioxidant activity of tea leaf and orange peel extract in In Vitro and In Silico. This research includes extraction process of orange peel and tea leaves using maceration method. TLC test was done using silica gel, antioxidant using DPPH method and in silico test was done using Autodock Vina Software by docking the tangeretin and kaempferol compounds to the Bcl-xl protein target and tablet dosage formulation test. The results of this study showed antioxidant activity in breast cancer cells with IC50 as much as 83.00 μg / ml. In molecular docking, the kaempferol compound has an affinity of -6.4 and -6,7 kcal / mol, the tangeretin compound has an affinity of -5.8 and -4,5 kcal / mol. In the TLC results, the Rf value found in orange peel extract was 0.87 and tea leaf extract 0.65. It can be concluded that the combination of ethanolic extract of orange peel and tea leaves has the potential as an antioxidant.