Abstract In the present work the gasification process of cork residues sourced in an industrial procedure in the regions of Extremadura (Spain) and Alentejo (Portugal) was studied. These by-products were classified as black agglomerates (low and high granulate), sandpaper dust (white agglomerate) and triturated wood. Samples of several residues obtained through different phases of the cork manufacturing process were collected and next quantified. In order to test their ability to produce energy, all the referred residues were gasified. The air flow was varied, ranging from 50 up to 400 cm 3 min −1 . The thermal treatment temperature was also varied from 650 °C up to 800 °C. The experimental results indicate that the optimal conditions in terms of energy production were an air flow equal to 200 cm 3 min −1 and a treatment temperature of 800 °C.