Abstract: The present invention relates to a time sync-type One-Time Password (OTP) generation device and method for a mobile phone. The present invention is configured such that an IC chip, in which a serial number and a secret key for OTP generation are encoded and stored, is mounted in an IC interface provided in the battery mounting part of a mobile phone, and is configured such that a decoding unit for encoding the serial number and secret key of the IC chip, a time counter for counting time information provided from a base station, and an OTP generation module for generating OTP numbers using the time information, the serial number and the secret key as a key value for an OTP program are included in the mobile phone. Accordingly, in accordance with the present invention, it is not necessary for a user to carry a separate OTP generation terminal, and concerns with respect to the hacking of OTP numbers can be alleviated because a serial number and a secret key are stored in an IC chip that cannot be hacked.