The structure of disordered gain media for a two-dimensional random laser was designed to obtain the specified spectrum of the emitted light. A scattering medium with a checkerboard structure was used to produce random lasing. Structural optimization was performed using a direct binary search method. The simulation results show that the emitted light can be concentrated at a single wavelength or within a specific wavelength range. The effect of the pump rate and manufacturing errors on the optimized spectrum of the laser emission was also examined. In this paper, we propose a new design scheme for achieving laser emission with any specified spectral shape by considering a multiple scattering medium as deterministic cavities. •A new design scheme for achieving specified laser emission using random structures proposed.•Laser cavities with a checkerboard structure designed aiming for high figures of merit of the emission spectrum.•Effects of the pump rate and manufacturing errors examined.