Cheil Industries Inc. is well known as one of the typical fabrics and fashion company. But there are not so many people who know that Cheil Industries Inc. stands out in chemical business field.Now Cheil Industries Inc. is diversifying to fabrics, fashion, chemical and IT materials industry. In late end of 80’s, on account of intensive investigating in chemical and IT materials industry, Cheil Industries Inc. could get away from fixed idea and also now chemical business was situated in the center of Cheil Industries Inc. business field as “future business”.Cheil Industries Inc. is showing outstanding outcome both chemical and IT materials industry, and it shows us successful result in its diversification.This case study is to investigate key factors that Cheil Industries Inc. achieved success in diversification. Based on the investigation, we discuss future course.