Abstract: Conventional viscosity measurement instruments cannot guarantee the high-pressure and low-temperature conditions for the stable existence of hydrate slurry, resulting in failure of accurate and effective measurement of viscosity of hydrate slurry. This paper presents the theoretical calculation and experimental measurement methods of hydrate slurry viscosity and analyzes the measurement principle of viscometer. It points out that there is a linearly proportion relationship between torque and viscosity for any experimental system. So, through calibrating standard torque-viscosity relationship, torque meter can be used to read torque during experiment and then the viscosity of hydrate slurry can be obtained according to the linear relationship. Moreover, experimental scheme is designed to use three prediction models proposed in literatures as theoretical models and then the measured results are compared with the theoretical calculation results. The results show that this method is simple and can realize quick and accurate measurement on the viscosity of hydrate slurry