The utility model discloses a premelting pot system, which enables aluminum-zinc liquid in a runner to maintain better flowability and comprises the runner connected with a premelting pot, wherein a gas heating device is arranged at an opening of the runner and comprises a gas delivery pipe and a combustion pipe communicated with the gas delivery pipe; the combustion pipe extends in the length direction of the runner; and gas spray ports are uniformly distributed on the combustion pipe. The combustion pipe comprises at least two sections; a gas branch pipe is arranged between the gas delivery pipe and each section of the combustion pipe; and an adjusting valve is arranged on the gas branch pipe. A cover plate is paved on the opening of the runner; and an air sucking port is formed on the cover plate. The cover plate comprises a support structure and a heat-insulating layer in the support structure. The premelting system is applicable for a production line for continuous hot-dip aluminum-zinc coating.