Water management efficiency is a key issue for sustainable agriculture development, since it is necessary to get a higher biomass production per unit of applied water. This study aimed to determine both water requirements and water use efficiency (WUE) and their effect on yield and quality parameters in carrots (Daucus carota L.), during the 2006 - 2007 growing season in Chilian, Chile (36° 35' 43.2" S, 72° 04' 39" W, 140 m altitude). The water treatments applied were 25, 50, 75, 100 and 125 % pan evaporation (Epan) in a Haploxerand soil under drip irrigation. The results showed that the highest crop yield was obtained with 100% Epan treatment. However, the highest WUE was found in the 75% Epan treatment equivalent to 3864 m³ ha-1, which is the recommended water application level in irrigation scheduling. Regarding carrot crop yield and quality parameters, statistical differences between the different water treatments were not significant, but the increase of applied water (125% Epan) reduced plant density and root length. This relationship between yield and applied water will allow to improve the management of water resources under water scarcity.