PURPOSE: To provide an installation device for reducing exposure of a worker generated when a drum can filled with low level radioactive metal wastes is installed in a melting furnace.

CONSTITUTION: An installation device of material to be melted of a melting furnace is composed of an upper gate 5 for opening/closing the upper installation port of a chamber 1 provided on a ceiling wall 25 of a closed bulkhead in which the melting furnace is stored, an electric winch 4 mounted in a box provided on the upper gate 5, a swinging tool 30 of a drum can 10 filled with low-level radioactive metal wastes, mounted on the lower end of a hoisting wire 35 of the electric winch 4 hung through the opening formed on the upper gate 5, a lower gate 6 for opening/closing the lower opening of the chamber 1, and of a hydraulic or pneumatical cylinder for opening/closing and driving the upper and lower gates. Since the gates are provided in a dual mode, diffusion of contaminated material to a safe division is prevented, and the swinging tool can be safely replaced.