Steam box

The invention discloses a steam box, and relates to the technical field of kitchen ware. The steam box comprises a box body, a heat dissipation device, a purified water preheating pipeline and a steam generator, an inner container is arranged in the box body, the heat dissipation device is arranged on the upper portion of the inner container, the heat dissipation device comprises a heat dissipation air channel and a fan communicated with the heat dissipation air channel, and the fan is used for conveying working airflow into the heat dissipation air channel; the purified water preheating pipeline is arranged in the heat dissipation air duct, is communicated with a purified water source and is used for preheating purified water; purified water preheated by the purified water preheating pipeline is conveyed into the steam generator to generate steam, and the steam generator is communicated with the inner container so as to guide the steam into the inner container. The purified water is preheated by exchanging h