Input of Tibetan characters on mobile phone poses a great significance to the mobile communication of Tibetan areas. The article proposes a mobile phone input method based on syllable word and implements the globe's first input method software for Tibetan characters on mobile phone. On the basis of analyzing the basic structure of Tibetan characters and the specific demands of mobile phones, we design the syllable word-based input method coding scheme, keyboard layout and software for Tibetan characters, and implement the complete Tibetan input method system on a mobile phone running Windows CE, enabling it for the receiving and sending of SMS. Finally suggestions for improvement are made to boost the efficiency and enhance functions of the Tibetan input method.