Abstract: Based on the time domain reflection technique and transient hotwire thermalphysical measurement technique, a gas hydrate experimental equipment has been designed to measure the thermalphysical properties of gas hydrate in porous media under high pressure. Hydrate is synthesized in porous media which particle size is between 0.18~0.25 mm, and 0.3 g/L sodium dodecyl sulfate (SDS) is added into the system as surfactant. The gas source is methane (99.9%). The thermalphysical properties of hydrate were detected in the sediment layers. The heat conduction rate measured by cross hotwire method is (1.112±0.080) W/(m·K) and the result measured by parallel hotwire method is (1.078±0.057) W/(m·K).