The aim of this work is to calculate and compare the economic efficiency indices of irrigated farms and the level of optimisation of irrigation water used for the main crops of the Gharb area. To this end, a Data Envelopment Analysis (DEA) model was used to calculate efficiency indices. The survey covered 49 farms with different crop systems (vegetables, citrus crops, cereals, forage, sugar beet and sugar cane) and different irrigation systems (drip, sprinkler and gravity-fed). The results show that the most efficient farms are both those affected by water stress and those with “unlimited” access to water resources (private pumping). On the other hand, 73 % of the farms are inefficient, indicating that the majority of farmers do not have a good grasp of the available technology.