The outer pericarps of Lecythis pisonis Camb. are by-products with a high content of antioxidant substances. The goal of the present study was to analyze the incorporation of L. pisonis pericarp extract in an all-natural formulation. Physical-chemical and organoleptic characteristics and Challenge tests were evaluated before and after the stability test of the cosmetic formulation. The instability of the formulation increased with the increase of the concentration of the extract. The physical-chemical and organoleptic parameters did not present alterations after the stability test. The extract of the outer pericarp of L. pisonis seems to be compatible with the cream formulation. However, the concentration should be analyzed to not interfere with the stability of the product. The natural formulation developed is under the legal requirements of the National Agency of Sanitary Monitoring of Brazil (Agência Nacional de Vigilância Sanitária), presenting an efficient conservation system.