Abstract: Influence of different H₂S contents on pressure and temperature of natural gas hydrate formed in wet gas pipeline is researched with statistic thermodynamics method, and process simulation on variation Iaw of pressure and temperature of high-sulphur wet gas pipeline is carried out by means of HYSYS software. Results show that the more H₂S content is, the easier hydrate forms variation tendency between pressure and temperature in high-sulphur wet gas pipeline is similar, the existence of water phase intensifies the variation of pressure and temperature of pipeline, and hydrate is easier to form at uphill pipeline; under the condition of high pressure, low water phase content would form saturated free water environment and even gas stream with relatively high water phase content is easier to form hydrate.