An undescribed disease occurred on endive, Cichorium endivia L., in Iwate Prefecture in July 1999. Pathogenicity was demonstrated in a fungal isolate obtained from diseased plants. The isolate was identified as Rhizoctonia solani Kühn AGl-IB, based on morphological and cultural characteristics and anastomosis grouping test. Bottom rot of endive caused by R. solani Kuhn AG1-IB is pröposed as a new disease.