This paper presents a solution of mobile payment based on SWP/HCI (ETSI) implemented with Micro SD card connected to an NFC-enabled mobile phone. Connection scenarios of the solution are described. Moreover, SWP/HCI protocol architecture is given. Programming and optimization of this solution is analyzed as well. We implement the functions and procedures using C plus plus language on ARM 7 platform. This solution complies with the development of NFC technology and compatible with the existing POS payment system terminals. And after optimization, the occupying RAM space of the codes is reduced by 74%.