The invention relates to the technical field of loading and unloading devices, and in particular relates to a horizontal automatic mechanical loading and unloading device for a reducing tank. The device comprises a first supporting column and a second supporting column, wherein a second fixing seat is arranged at the outer side of a rotating shaft; the upper ends of the second fixing seat and a first fixing seat are fixedly connected to a reducing tank body; a feeding port is formed in the upper end of the reducing tank body, and a first discharging port is formed in the lower end of the reducing tank body; a second discharging port is formed in one side, far away from the first supporting column, of the reducing tank body; a pushing ring fits the inner wall of the reducing tank body, andthrough holes are uniformly formed in the lower part of the outer side of the pushing ring; a first cylinder, a solenoid valve and a second cylinder are connected to outer control switches. The deviceis simple in structure; manual operation is replaced, so that the working efficiency is improved; and meanwhile, the residues inside can be efficiently removed, so that the next sintering is not influenced, and the materials are not wasted, and as a result, the practicability is improved; and the device is worthy of popularization and application in future.