Irrigation is a way of increasing yield and shoot growth in olive trees. In this work, the influence of irrigation on a traditional rainfed olive orchard (cv Cornicabra) has been studied using olive trees fifty years old, planted at a distance of 12 x 12 m in Almodóvar del Campo (Ciudad Real, Spain). Shoot growth, crown volume, yield, size and humidity of fruit and flesh/pit ratio were measured. Irrigated trees showed an increase in yield and shoot growth only during the last year of the experiment (2002).