In order to investigating effect of irrigation intervals on yield and yield components of sorghum cultivars, an experiment was conducted at the Research Farm of Islamic Azad University of Miyaneh on May, 2008. This experiment was implemented in the form of split-plot with randomized complete block design in three replicates. The first factor included 3 irrigation intervals (7,14,21) days, and grain sorghum cultivars including Kimya, Payam and broom sorghum called local cultivar Golbous was main and secondary plot, respectively. According to the results, the effect of irrigation intervals and cultivar on many of the studied traits such as plant height, panicle length, stem diameter, number of leaves, grain number per plant and grain yield was significant and intraction between irrigation intervals and cultivar on plant height, panicle length, grain number per plant was significant. The comparison of means indicated that plant height, panicle length, grain number per plant and grain yield decreases as the irrigation intervals increased. This comparison also suggested payam cultivar is superior to Kimya and local Golbous in terms of the grain number per plant and grain yield. Plant height had a positive and significant correlation with all of the studied characters unless seed number per plant