ABSTRACT The search for phytotherapeutic products used to treat multiple diseases represents an area of great interest. However, its correct use must be ensured with the lowest possible risk to health. Since, extracts of vegetables used for medicinal purposes that have mutagenic and carcinogenic activity are known. The present study evaluated the cytotoxic and genotoxic effect of the aqueous extract of Physalis peruviana L. (golden berry) at concentrations of 10, 20 and 30mg / ml on Allium cepa (onion) meristematic cells and at concentrations of 62.5, 100, 250 and 1000 ug/ml on human lymphocytes. 12 onion bulbs were used, subjected to extract concentrations of 10, 20 and 30mg/ml and a control group (3 repetitions each), then coloration, assembly and microscopic reading were made at 400 and 1000x, evidencing the decrease of the mitotic index and phase index in the concentrations evaluated...