Abstract: Irrigation water requirement, irrigation times and numbers, evapotranspiration (ET) and water-yield (Y) relationship of tomato (Lycopersicon esculentum, SC 2121 variety) were investigated. Treatments included irrigations at 14 (T14), 21 (T21) and 28 (T28) days intervals. Because there was no statistically significant difference in the yield between treatments, T28 treatment was suggested to practice. Seasonal ET of T28 was measured as 668 mm while the highest monthly ET was recorded in July as 223 mm. A total of 370 mm irrigation water was applied and 76010 kg ha -1 yield was obtained from this treatment. Using seasonal ET and average yields of the treatments, water-yield relationships were explained in the from Y = 98.455 ET + 10956 (Y: yield in kg ha -1 and ET: evapotranspiration in mm).