Abstract: Considering the influence of hydrate particle volume fraction on viscosity of hydrate slurry, information about hydrate slurry in horizontal pipe under the design conditions are obtained by CFD/FLUENT simulation, including flow pattern, bed height, distribution of particle volume fractions, pipeline pressure drop, average viscosity and so on. And at the same time, based on the double layer flow model for solid-liquid two-phase flow proposed by Doron P, flow parameters under various conditions are solved by program. Contrasted to the simulation results, calculation results and experimental results, we find that numerical simulation method can accurately predict the flow pressure drop of hydrate slurry in horizontal pipe. Taking the hydrate particle size distribution into account by programming UDF, the flow condition of hydrate slurry can be described better. Therefore, numerical simulation can be used as an effective method for studying the flow behavior of hydrate slurry in horizontal pipe and analyzing the factors affecting flow parameters, but it has some defects to be improved.