The transmission and frequency characteristics of the micro-laser with photonic crystal waveguide were analyzed in this paper based on the finite-difference-domain(FDTD) method. The results demonstrate that, compared with the pure random media or pure photonic crystal waveguide, the light in defect area with random media is obviously amplified, meanwhile the localization level becomes higher either. On the other hand, the interaction time between the random gain medium is prolonged, the loss and the threshold is reduced. In addition, the light can be modulated by the triangle lattice photonic crystal. The design of new device in this paper lay a theoretical foundation of integrated optical system and micro-laser with low threshold.