Abstract: RHF(Rice husk fiber, RHF) was added into cement as reinforced materials to prepare RHF/cement composites.The effect of particle size on the dispersion properties of RHF in cement matrix was studied. And take the particle size and mass ratio of RHF to cement as factors, the density, flexural strength, water content, water absorption and thermal conductivity of RHF/cement composite as response value, the mathematical model was established using the response surface method, the molding process of RHF/cement composites was optimized. The results show that the smaller particle size of RHF, the better dispersion of RHF in cement, the dispersion coefficient reaches the maximum value of 0.981 when particle size is 150 μm.The response surface model analysis shows that the RHF/cement composite achieves optimal when particle size is 150 μm and mass ratio is 3%, under this process, the density, flexural strength, water content, water absorption and thermal conductivity of RHF/cement reach 1 559 kg/m³, 9.38 MPa, 7.05%, 16.71%, and 0.50W/(m·K), respectively, which are all up to JC/T 411-2007.