The invention provides a wireless printing system capable of guaranteeing the reliable transmission of data, which comprises a personal computer (PC) client end which is provided with a printing server and a printer end which is provided with a data receiving module, wherein the printing server comprises a printing task managing module and a printing driving module, the printing task managing module receives a printing order and transmits the printing order to the printing driving module, the data are transmitted by the printing driving module to the printer end through an interface which can guarantee the data transmission accuracy and uniqueness, and the wireless printing system can guarantee the completeness of the data under the situation of the wireless printing.