The permeability of porous media is one of the critical parameters that determines gas recovery from natural gas hydrate reservoirs. We measured the permeability of quartz sands by injecting water at a certain flow rate. In hydrate-bearing sands, the larger the hydrate saturation, the smaller the shape factor in the presence of hydrate. A k(r) - S-H relationship with the hydrate saturation both lower and higher than 10% was obtained. Based on the experimental results, the saturation exponent n varied from 6.0 to 1.0. (C) 2018 Elsevier Ltd. All rights reserved.