To provide a keyboard and key data information processing system in which keying can be processed rightly as "KANA" character of (consonant + vowel) when it is erroneous keying within a predetermined time even if a vowel key is erroneously keyed a little faster because of a low extent of a simultaneous keying skill in the keyboard wherein vowel keys are arranged in the area where keying can be performed only with a left hand or a right hand, and consonant keys are arranged in the area where simultaneous keying (strictly, a little faster keying of consonant keys) can be performed with the other hand, and the system using such a keyboard.

A vowel data signal is outputted to a key data information processing control section while being delayed for a predetermined time in comparison with data signals of other keys.