A method and apparatus for selectively key-inputting a Kanji (Chinese and Japanese ideogram) in a Japanese sentence are disclosed. The operator keys-in a reading of a desired Kanji through a keyboard, and candidate Kanjis for that reading are displayed on a display screen so that the operator chooses a relevant Kanji for entry out of the displayed candidate Kanjis. In entering the reading of a Kanji, blocks which are in correspondence to character keys located in home positions of the keyboard and in the neighborhood thereof are displayed on the display screen and candidate Kanjis corresponding to the reading of the desired Kanji are displayed in the blocks. The operator then keys a character key corresponding to a relevant candidate Kanji displayed on the display screen.