Embodiments of the present specification provide a data transmission method and apparatus, where the data processing method includes: sending a first preset number of sub data packets to a receiving end; setting data information of a first sub data packet in initial sending status information to obtain first sending status information, and constructing an association relationship between the first sending status information and a corresponding field in a sending information maintenance table; in a case that confirmation information returned by the receiving end is received, determining a second sub data packet corresponding to the confirmation information, and determining second sending status information corresponding to the second sub data packet, and removing an association relationship between the second sending status information and a corresponding field in the sending information maintenance table. In this way a reliability of data transmission may be improved.