To study the effect of planting date on root rot disease caused by Fusarium solani f.sp. phaseoli of Chitti bean (Phaseolus vulgaris L.), an experiment was conducted in Khomein Bean Research field Station in 2004 and 2006 cropping seasons. This experiment was arranged as split plot in a randomized complete block design with three replications. Three chitti bean genotypes (local Khomein, Talash, and COS16) were sown in four different planting dates (10 May, 25 May, 09 June, and 24 June).Combined analysis of variance showed that the effect of planting date on seed/pod, seed/plant, 100 grains weight, seed yield and root rot disease severity was significant at the 1% probability level and on pods/plant at the 5% probability level. Effect of cultivar on pods/plant, grains/plant, 100 grains weight and root rot disease severity was significant at the 1% probability level and on grains/pod and grain yield at the 5% probability level. Planting in 09 June and COS16 genotype produced the highest seed yield. Delaying planting date decreased disease severity. COS16 and local Khomein genotypes had the least and the highest disease severity, respectively.