The invention discloses an SDIO-WIFI data transmission method and system with a buffer area. The method comprises a step of receiving data, packing the data into a data packet, and then writing the data packet into the buffer area of a first-in-first-out format, a step of reading the data packet from the buffer area, parsing the packet, getting the data, and then sending the data to an externaldevice from an SDIO interface. According to the method, the data sent by a WIFI driver to an SDIO driver is cached through the buffer area of the first-in-first-out format, the WIFI driver can process other data without waiting for the SDIO driver to send the data, the WIFI throughput efficiency is improved, the throughput jitter is small, the delay can be reduced at a terminal, and the communication efficiency is improved.