This study was conducted to determine the most suitable irrigation frequency and quantity in cucumber grown under field conditions. The amount of water used was based on pan evaporation from a screened Class-A pan. Irrigation treatments consisted of two irrigation intervals (I1: 4 and 12: 8 day), and three plant-pan coefficients (K(cp)1: 0.50; K(cp)2: 0.75 and K(cp)3: 1.00). Plants were first watered at the transplanting date and scheduled irrigations were initiated after 4- and 8-day intervals.