It is not so easy even for the ordinary Chinese to spell the correct Pinyin. Therefore the Pinyin-based Chinese character (Kanji) input system including the Chinese word processor is not easy to use. This paper propose a FEP (Front End Processor) to the Pinyin-based input system which allows the user's slight mistakes due to his ignorance of the spelling or dialect. This FEP uses the similarity of the structure of Kanji to confirm the correct Pinyin.