The present work describes comparative dilute acid pretreatment of the argan pulp (residue produced during the argan oil extraction) used as an economical source for bioethanol production. Response surface methodology was used to optimize the pretreatment process and to explore the effect of operational parameters (acid concentration, temperature, time and biomass loading), depending on the acid type (HCl, H2SO4) and pretreatment approach, on total and reducing sugars recovery, in addition to phenolic compounds rate as inhibitors produced during pretreatment process. Experimental results predict an optimal yield of total and reducing sugars of 171.46 mg/ml and 54.83 mg/ml, respectively, were achieved at an optimized time of 30 min with 7% of sulfuric acid at 160°C using 40 % for biomass loading.