Associated gas silicon gel dehydration and drying is a method of removing moisture from associated gas by using solid adsorption. The two-tower + auxiliary tower process flow is used, and the regeneration of adsorbent is achieved by changing the pressure or temperature of the adsorbent. It can deeply remove water from natural gas to make the water dew point able to be reduced to below -70 ℃, which is generally suitable for the dehydration of low flow gas, and has the advantages of simple process and large operating flexibility.