Studies carried out in different native Chilean plants demonstrate that compounds found in both fruits and leaves have the capacity to decrease oxidative cellular damage in humans, thus contributing to the prevention of chronic illnesses such as diabetes, cancer, and arterial hypertension. Information on native Chilean medicinal plants was extracted from the Scopus, Science Direct, Google Scholar, and PubMed databases. Plants with relevant antioxidant activity were selected based on their chemical compounds and their use as native-flora research materials in Chile. Provitamin A, carotenoids and vitamins C and E are the main compounds found in the studied species. Several analyses also show the presence of polyphenolic and alkaloid compounds with proven capacity to increase antioxidant activity. Therefore, such native species should be of interest for the food, cosmetic, and pharmaceutical industries, as safer natural antioxidant compounds are crucial for the prevention of human illnesses and for replacing the synthetic antioxidants currently in use (BHT, BHA). The present review aims to provide up-to-date information on the traditional uses of native plants in popular medicine, and to present evidence concerning the antioxidant activity of the studied plant species and their relationship with the active principles found.