This study was performed at olive orchard at the Engineering College, University of Salahaddin- Erbil, Kurdistan, Iraq, during the growing season 2000-2001, on a sandy silty loam soil. The objectives of this study were to find out the responses of olive trees (Olea europaea L. cv. Ashrasie) to five irrigation frequencies (0,1,2,3 and 4) during drought season and to determine their effects on tree growth and yield. Numbers of replicates were three trees as a replicate. Forty-five trees of fourteen years old, Ashrasie cultivar were used, each nine uniform size trees distributed randomly among the 5 treatments in RCBD experiment. Irrigation treatments carried out at monthly intervals during the dry season, starting on June 1, by constant amounts of water for each treatment up to reach 60 cm soil depth to field capacity, using basin irrigation method. Irrigation treatments resulted significant increases in the shoot elongation and thickening percentages, leaf area at harvest, fruit yield and quality characteristics. As well as oil contents. The highest values of shoot elongation and thickening percentages were achieved when three irrigation treatments were used, while the best results of each leaf area at harvest, as well as oil content fruit quality characteristics such as fruit weight and size, pulp/stone ratio, were obtained from fourth irrigation treatment.