The mechanical properties and mechanical stabilities of pipewall hydrate deposition are of great importance to the prevention and removal of pipeline hydrate plugging. In this paper, the mechanical properties and mechanical stabilities of pipewall hydrate deposition are quantitatively investigated by modelling and numerical simulation. First, a structural model for pipewall hydrate deposition is established based on particle packing theory. Using this structural model, the main mechanical parameters of pipewall hydrate deposition can be calculated. Then, numerical simulations using finite element method and ANSYS Mechanical APDL 14.5 are conducted based on the calculated mechanical parameters. Through the simulations, the structure deformation, internal stress distribution and failure of pipewall hydrate deposition when it is under the action of external forces are studied and the influences of flow rate, deposition thickness and deposition length are investigated. The results of this paper can provide guidance for pipeline flow assurance. (C) 2018 Elsevier Ltd. All rights reserved.