Mobile payment system and method

The present invention discloses a mobile payment system installed on a mobile device (such as a mobile phone). The mobile payment system comprises a card reading device and a secure payment unit, wherein the card reading device is configured to acquire information of a magnetic stripe card, and the secure payment unit is configured to generate changing magnetic field information in accordance with the information of the magnetic stripe card, so that interaction with a POS terminal is performed. The present invention also discloses a method for carrying out card information transmission by using the mobile payment system.