In April 2009 two wheat cropping fields, Jeonju and Gimje in Jeonbuk Province, showed yellowish leaves and dead tillers in stem bases with sharp lens-shaped darken lesions. The disease incidence in wheat cultivar Jopummil ranged from 2.2 to 43.5%, with a mean incidence of 28.5%. The different incidence was related the seeding date. Earlier seeding (15th October) fields showed severe incidence as 25.5 to 43.5% while late seeding around the end of October weakened incidence in the cultivar. Based on morphology and pathogenic characteristics, the fungus was identified as Rhizoctonia cerealis that causes sharp eyespot in wheat. The disease severely affected growth and yield including culm length, spike length, number of kernel. The average culm length of the infected cv. Jopummil was 66 cm while that of healthy plant was 74 cm. The number of kernel and tiller per unit area was decreased only in the case of more than 13% incidence, but the length of heads was not significantly different compared with that of the healthy plants.