PURPOSE: To provide a device for supplying a solid substance to be burnt, which is capable of being supplied stably by transporting a gas of comparatively low pressure without necessitating any special mechanical facility, into a combustion furnace.

CONSTITUTION: A substantially horizontally or downwardly extended straight chute 2, provided with a charging port 8 for charging a solid substance to be burnt at the upper part thereof and whose terminal end is opened in a combustion furnace for burning the substance to be burnt at an opening 5, is provided with the blowing port B of gas along the axis C of the chute from more upstream side than the charging position A of the substance to be burnt while the inner diameter of the chute 2 is at least two times of the average grain size of the charged substance to be burnt and is larger than the maximum grain size of the same. In this case, the flow speed of a blown gas in the chute is preferably not lower than 20m/s.