A kind of multitap complex coefficient microwave photonic filter was proposed based on novel tunable multi-wavelength fiber laser and stimulated Brillouin scattering(SBS). The complex coefficient was realized based on a phase shift introduced by SBS. The phase shift was controlled by adjusting the pump power of SBS, and so the center frequency of the filter was adjusted continuously. 16 laser signals with wavelength intervals of 0.338 nm were obtained based on a tunable multi-wavelength high erbium doped fiber laser in experiment. And then, the influence on this filter by the length of SBS gain medium, the number of the taps and the wavelength interval were researched by simulation.