An OFDM transmission apparatus having minimal transmission delay comprises a training symbol storage and generation unit, a delay unit and a controller. The training symbol storage and generation unit stores training symbols for the preamble, and outputs the stored training symbols when a training symbol output request signal is received. The delay unit receives data for the signal field from the MAC layer, delays the received data by the data processing time of the scrambler, and outputs the delayed data to the convolution encoder. The controller outputs the training symbol output request signal, requesting the preamble of the frame, to the training symbol storage and generation unit when a frame transmission request is received from the MAC layer, and outputs a data request signal, requesting the signal field and the data field, to the MAC layer in consideration of total data processing time (TPROCESS).