Since ancient times, plants have been used as preservatives, spices, flavorings and as natural remedies to prevent or treat diseases, thanks to the biological activity correlated with the bioactive compounds they contain. The avocado fruit (Persea americana), native to Mexico and Guatemala, has been traditionally used for its pleasant organoleptic characteristics, high nutritional value and health benefits, but its residual biomass (seed, skin and tree leaves) is also valuable in therapeutic terms. For this reason, the present investigation reviews the pharmacological potential of avocado waste. It can serve as a source of antioxidants, hypotensive, anti-analgesic, photoprotective, and anti-inflammatory agents, and to treat skin disorders. These properties are generally attributed to the phenolic composition. The content of phenolic compounds in avocado waste extracts varied between 16 and 307 g/kg dry weight, depending on the waste type and extraction conditions, among others. In particular, our results suggested that using water as solvent, high amount of phenolic compounds can be obtained from the peel (266 g/kg dry weight) and it was correlated with a major antioxidant activity. Thereby the peels can be applied to obtain antioxidants and water can be used as an environmentally friendly extraction solvent for food and pharmacological applications.