The invention provides a current fusing-based polycrystalline fuse circuit, which is applied to a semiconductor integrated circuit and mainly solves the problem that the area of the conventional polycrystalline fuse circuit is too large. The polycrystalline fuse circuit comprises a polycrystalline fuse, a fusing control circuit and an output converter, wherein the polycrystalline fuse is connected in series between a power supply of an external semiconductor integrated circuit and a fusing control structure; the fusing control circuit consists of an NMOS transistor buffer and an NMOS transistor level stabilizer and is connected in series between the polycrystalline fuse and the ground to generate large current required by fusing the fuse; the output converter consists of a phase inverter;and the input end of the output converter is connected with the fusing control circuit and the polycrystalline fuse, while the output end is used as the output of the polycrystalline fuse circuit to ensure that the polycrystalline fuse circuit outputs a standard digital logic level. The area of the polycrystalline fuse circuit is reduced, the chip area is saved, the chip cost is reduced and the polycrystalline fuse circuit can be used for maintaining and regulating the semiconductor integrated circuit.