To study the effect of laser processing parameters on the surface texture morphology of Ni-Co-Si₃N₄ composite coating, we used an electrodeposition technique to prepare the Ni-Co-Si₃N₄ composite coating on the 45 steel surfaces and then processed the coating by optical fiber laser with 1070-nm wavelength. We studied the influence of pulse energy density, pulse width, and pulse number of laser on microstructure by single-factor method, obtaining the evolution law of characteristic parameters such as inside diameter, outside diameter, center point height, edge height, and nadir height of microstructure. The results showed that the laser interacts with the Ni-Co-Si₃N₄ composite coating, forming four typical morphologies: spherical-cap-shaped bump, W-shaped pit, crater pit, and pit with double concentric holes. The surface microstructure changed from spherical-cap-shaped bump to pit with double concentric holes because of the increased pulse energy density and changed from crater pit to spherical-cap-shaped bump because of the increased pulse width. Besides, the depth and edge height of the surface microstructure increased because of the increased pulse number.