Abstract: The development of shale gas well has the production characteristics of large gas production at the initial stage of production and rapid attenuation in the middle and late stages. The excessive processing capacity of triglycol(TEG) dehydration unit will cause the dehydration load to exceed the allowable range of the optimal working condition, the dehydration effect was not ideal. Based on this, the process simulation of the TEG dehydration unit was carried out using HYSYS software. The influences of lean TEG mass fraction and TEG circulation rate on the dehydration effect of the TEG dehydration unit were quantitatively analyzed. The actual assessment data on site under the different processing volume were compared with the simulation results to verify the accuracy of the simulation results. The results showed that in order to meet the production control index of the lean TEG mass fraction above 99%, the reboiler temperature should be appropriately increased and the stripping gas volume rate could be reasonably increased in the range of 15-25 m³/h on the premise that the regeneration temperature did not exceed the thermal degradation temperature of 204 ℃. When the mass fraction of lean liquid was higher than 99% and the water dew point was far lower than the design value, it was suggested to reduce the total circulation volume of lean TEG under the premise of ensuring the water dew point of product gas to reach the standard, so as to reduce the fuel gas consumption and energy consumption of reboiler.