Abstract: A wireless keypad equipped with no power source (rechargeable battery or the like) that contributes to reducing the weight, thickness and size and a keypad system, liberating the user from the work and from the burden of cost. The keypad system includes a keypad having a plurality of input keys and one or a plurality of RF-IDs corresponding to the keys, and a host unit including RF-ID read means which is connected to the keypad in a wireless manner through the RF-IDs to read key data stored in the RF-IDs, and control means which is connected to the RF-ID read means to execute the operation inclusive of control operation upon obtaining the key data from the RF-ID read means.