Provided by the present invention are a data transmission method and a terminal, and the method comprises: acquiring data to be sent comprising N data frames; acquiring a bit sequence of an ith data frame; sending X waveform sequences corresponding to bits in the bit sequence of the ith data frame; detecting a level change of a receiving port after completion of sending the X waveform sequences; determining Y waveform sequences of received data; determining a bit sequence of the received data; acquiring a bit sequence of an (i+1)th data frame when the bit sequence at least comprises a flag bit for at least indicating success of receiving data; sending Z waveform sequences corresponding to bits in the bit sequence of the (i+1)th data frame until all the N data frames of the data to be sent are sent.