The invention provides an FBMC (Filtered Bank Multi-Carrier) symbol modulation and demodulation method and device. The modulation method includes executing carrier mapping; performing inverse Fourier transform on a combined frequency domain sequence so as to obtain a time domain sequence of FBMC symbols subjected to modulation, executing at least one operation among the below during the carrier mapping executing process so as to enable the time sequence of a Q-channel FBMC symbol in the time domain sequences of the FBMC symbols to offset odd number times of a half of the total carrier number of the symbol sequences than the time domain sequence of an I-channel FBMC symbol in the time domain sequences of the FBMC symbols subjected to modulation: multiplying even number symbol sequences and odd number symbol sequences among the I-channel FBMC symbol sequences respectively by a preset first linear phase and a preset second linear phase, and multiplying even number symbol sequences and odd number symbol sequences among the Q-channel FBMC symbol sequences respectively by a preset third linear phase and a preset fourth linear phase. By adopting the above scheme, FBMC symbol modulation and demodulation complexity is reduced.