Abstract: Particulate reinforced titanium matrix composites have broad application prospects in aerospace and other fields. The thermal-fluid behavior and the distribution of the ceramic particles in the deposited layer during the laser melting deposition of TiC/TC4 composites were studied by combining simulation and experiment. The results show that the process parameters have a significant effect on the thermal-fluid behavior of the molten pool and the morphology of the deposited layer. With the increase of laser power, the molten pool size and the maximum fluid flow rate increase. As the scanning speed increases, the molten pool size and the maximum fluid flow rate decrease. The fluid flow on the surface of the molten pool is corrugated. The molten metal flows from the center of the molten pool to the periphery. The molten metal on the isothermal surface of the bottom of the molten pool flows from the periphery to the bottom, and the vortex flow phenomenon occurs. In the process of laser melting deposition, TiC particles penetrate the Marangoni convection zone on the surface of the molten pool and interact with the fluid in the molten pool. Finally, they may appear in the distribution of the agglomeration in middle-upper part, the agglomeration in middle-lower part and uniform distribution in the deposited layer.