The experiment was conducted in lysimeters by using four soil moisture regimes irrigated when 0 (field capacity), 20, 50 and 80 % respectively of the total available water con­tent was exhausted to evaluate the soil water availability to sugar cane variety PR 61- 632. The lysimeters were covered with polyethylene selter to avoid the interference of rain­fall. It was designed in a latin square with 4 replications. The evapotranspiration rate de­creased sharply with decreasing soil water available water content. Plant population and stalk elongation were reduced significantly when soil available water was lower than 50%. As a result, both cane and sugar production of two dry treatments were signi­ficantly lower than that of two wet regimes. For scheduling purpose, it is suggested that this variety should be irrigated when 45% of the total available water is exhausted and the K factor is 0.35 when cane is younger than 4 months and is 1.0 for the rest of the growth period.