An apparatus for feeding raw material bars to a furnace body of a melting furnace, said apparatus being characterized by: an enclosure body provided with a feed passage that extends vertically and that is to be disposed above an open top side of the furnace body; a feeding unit including a push mechanism that extends vertically into an upper part of the feed passage, and a material retarder that extends into a lower part of the feed passage; and a transferring unit disposed at the enclosure body and configured to transfer a raw material bar to the feed passage in a manner that the raw material bar extends vertically in the feed passage with the push mechanism being disposed above the raw material bar and with the raw material bar contacting the material retarder; the push mechanism being operable to push the raw material bar in the feed passage downwardly and the material retarder being configured to retard downward movement of the raw material bar out of the feed passage and into the furnace body; the enclosure body further having an access passage; the apparatus further comprising a carriage that is movable into and out of the access passage and that is configured to hold the raw material bars; the enclosure body further having a gate mechanism that is configured to selectively open and close the access passage; the enclosure body being formed with at least one vent hole that permits high temperature gas from the furnace body to flow into the enclosure body for preheating the raw material bars in the enclosure body; and the material retarder including: a blocker that has an inclined face and a resisting part at a lower edge of the inclined face, the inclined face and the resisting part being disposed in the feed passage for contacting the raw material bar in the feed passage, a limit cage that is disposed at the enclosure body, a pair of fixing shafts, each having one end connected to the blocker and each extending slidably through the limit cage, and a pair of biasing components each sleeved on a respective one of the fixing shafts and each having opposite ends respectively abutting against the limit cage and the respective one of the fixing shafts, the biasing components biasing the fixing shafts for moving the blocker to project into the feed passage. an enclosure body provided with a feed passage that extends vertically and that is to be disposed above an open top side of the furnace body; a feeding unit including a push mechanism that extends vertically into an upper part of the feed passage, and a material retarder that extends into a lower part of the feed passage; and a transferring unit disposed at the enclosure body and configured to transfer a raw material bar to the feed passage in a manner that the raw material bar extends vertically in the feed passage with the push mechanism being disposed above the raw material bar and with the raw material bar contacting the material retarder; the push mechanism being operable to push the raw material bar in the feed passage downwardly and the material retarder being configured to retard downward movement of the raw material bar out of the feed passage and into the furnace body; the enclosure body further having an access passage; the apparatus further comprising a carriage that is movable into and out of the access passage and that is configured to hold the raw material bars; the enclosure body further having a gate mechanism that is configured to selectively open and close the access passage; the enclosure body being formed with at least one vent hole that permits high temperature gas from the furnace body to flow into the enclosure body for preheating the raw material bars in the enclosure body; and the material retarder including: a blocker that has an inclined face and a resisting part at a lower edge of the inclined face, the inclined face and the resisting part being disposed in the feed passage for contacting the raw material bar in the feed passage, a limit cage that is disposed at the enclosure body, a pair of fixing shafts, each having one end connected to the blocker and each extending slidably through the limit cage, and a pair of biasing components each sleeved on a respective one of the fixing shafts and each having opposite ends respectively abutting against the limit cage and the respective one of the fixing shafts, the biasing components biasing the fixing shafts for moving the blocker to project into the feed passage. a blocker that has an inclined face and a resisting part at a lower edge of the inclined face, the inclined face and the resisting part being disposed in the feed passage for contacting the raw material bar in the feed passage, a limit cage that is disposed at the enclosure body, a pair of fixing shafts, each having one end connected to the blocker and each extending slidably through the limit cage, and a pair of biasing components each sleeved on a respective one of the fixing shafts and each having opposite ends respectively abutting against the limit cage and the respective one of the fixing shafts, the biasing components biasing the fixing shafts for moving the blocker to project into the feed passage.