This work describes the feasibility of using almond shell as feedstock for bioethanol production. A pretreatment step was carried out using 4% NaOH for 60 min at 121 degrees C followed by 1% sulfuric acid for 60 min at 121 degrees C. Enzymatic saccharification of the pre-treated almond shell was performed using Penicillium occitanis enzymes. The process was optimized using a hybrid design with four parameters including the incubation time, temperature, enzyme loads, and polyethylene glycol (PEG) concentration. The optimum hydrolysis conditions led to a sugar yield of 13.5%. A detoxification step of the enzymatic hydrolysate was carried out at pH 5 using 1 U/ml of laccase enzyme produced by Polyporus ciliatus. Fermenting efficiency of the hydrolysates was greatly improved by laccase treatment, increasing the ethanol yield from 30% to 84%. These results demonstrated the efficiency of using almond shell as a promising source for bioethanol production. (C) 2016 Elsevier Ltd. All rights reserved.