Method and device for configuring a waveform at a transmitter are provided. The method includes: receiving at least one input signal, each input signal corresponding to a subcarrier spacing setting; performing IDFT pre-processing to each input signal, the IDFT pre-processing including DFT pre-coding or offset modulation; performing IDFT to each input signal which is subjected to the IDFT pre-processing, the IDFT including an IDFT with parameters including resource mapping and a corresponding IDFT size; performing IDFT post-processing to each input signal which is subjected to the IDFT to obtain at least one output signal, the IDFT post-processing including cyclic extension and time-domain windowing; adding the at least one output signal in time domain; and transmitting the added signal through a corresponding antenna port. Waveforms are configured flexibly according to practical scenarios at the transmitter to determine a most suitable waveform for current scenario, which meets practical requirements of 5G technology.