The invention discloses a steam furnace dry-burning prevention device. The steam furnace dry-burning prevention device comprises a furnace body. Bases are mounted at the bottom end of the furnace body; an evaporation structure is mounted at the bottom end inside the furnace body; a water tank is mounted at the upper end of the evaporation structure; a drainage pipe is mounted at one end of the bottom of the water tank; a drainage valve is mounted on the drainage pipe; a water inlet pipe is mounted above the drainage pipe, and a water inlet pipe valve is mounted on the water inlet pipe; a firstalerter is mounted at the other end of the bottom of the water tank, and a main switch control panel is mounted above the first alertor; a second alertor is mounted between the first alertor and themain switch control panel; a steam space is mounted at the upper end of the water tank; and a steam outlet is formed in the middle of the top end of the furnace body, a safety valve is mounted on oneside of the steam outlet, and a temperature detector is mounted at one end of the safety valve. The problems that when the water tank is lack of water, the steam furnace cannot stop heating and burnsin a dry mode, consequently, the steam furnace is damaged, and the potential safety hazard of the steam furnace occurs are solved.