In arid and semi-arid ecosystems, the efficient use of water becomes increasingly important because water is a crucial limiting factor for increased food and fibre production to supply an ever-growing number of people. A field experiment was conducted in three consecutive seasons three year in Mekhoni Agricultural Research Centre, Raya valley, to investigate with the objective of to evaluate the influence of supplemental irrigation applied at different growth stages on the yield, to prevent sorghum failure caused by less rain water and to maximize the water productivity of the sorghum. The experiment was laid out in a random complete block design (RCBD) consisting of eleven supplemental irrigation treatments (one supplemental irrigation during initial stage, one supplemental during development stage, one supplemental during mid-stage, one supplemental during Late stage, one supplemental during initial and development stage, one supplemental during initial and mid stage, one supplemental during initial and late stage, one supplemental during development and late stage, one supplemental during development and late stage and rain-fed (with no SI) as a control treatment with three replications. The result was showed a significant difference on plant height, panicle length, grain, biomass yield and water productivity sorghum. The highest grain yield was obtained from the treatment supplement one SI at development and mid stage and followed by one SI at mid stage and at late stage. Whereas, the lowest grain yield of sorghum was observed from treatment with rainfed (non-supplementary). It is concluded that in the study area the rain fed amount were very inadequate and supplementary irrigation will help to increase crop productivity, minimize crop failure due to the low rainfed. The experiment showed that supplementary irrigation offers a great potential for improving crop production in Raya valley.