Abstract: In the high pressure and low temperature conditions during production and transportation of subsea oil andgas, hydrate is formed easily, which could cause the risk of pipeline blockage. To investigate the phenomenon of pipelineblockage of fluid containing hydrate particles and the mechanism of particle flow with the continuous phase, a threedimensionalhydrate-contained solid-liquid pipeline model was established with the numerical simulation method based onCFD-DEM (Computational Fluid Dynamics-Discrete Element Method) coupling combined with the commercial softwareFluent and EDEM, giving consideration to the agglomeration of hydrate particles and the adhesion of particles on pipe wall.The condition that hydrate deposition on the pipe wall reduces the flow area during actual production was simulated usinga throttling element, and the flow state was analyzed at different velocity and aperture ratio. Thereby, the critical state ofblockage was defined for hydrate particle throttling pipeline, and the minimum aperture ratio of pipeline at different flow ratewas obtained, which provide a reference for the study on the risk of hydrate blockage.