Coconut is a tropical fruit largely consumed in many countries. In some areas of the Brazilian coast, coconut shell represents more than 60% of the domestic waste volume. The shell is composed mainly of lignin and cellulose with,chemical composition very similar to wood. As several kinds of wood are used as a phenolic source to produce extracts for artificial aging of alcoholic beverages, in this work, the coconut shell was evaluated as a source of phenolic compounds. The coconut powder was submitted to different toasting temperatures and the phenolic compounds were extracted by the application of ultrasound. The ultrasound extraction methodology has been studied as a low cost alternative in substitution to solvent reflux extraction. The experiments were done according to a factorial experimental planning and the effects of toasting time, toasting temperature and extraction time were evaluated through response surface methodology. The results indicate that high amounts of phenolics can be extracted from coconut shell by ultrasound assisted extraction technology. and that the extraction time was the most significant parameter for the process. (c) 2006 Elsevier Ltd. All rights reserved.