A routing structure of electrical wires (21, 22, 23), the routing structure comprising: multi-phase electrical wires (21, 22, 23) configured to carry electric currents with different phases; and a magnetic core (30, 40) having a ring shape, around which the electrical wires (21, 22, 23) are wound, wherein the magnetic core (30, 40) has a division type in which a first component (31, 41) constituting a part of the ring shape, and a second component (32, 42) constituting a remaining part of the ring shape are connected, wherein the electrical wires (21, 22, 23) with all phases are only wound around the first component (31,41); wherein the first and second component (31, 32, 41, 42) each have a columnar portion (31a, 32a, 41a, 42a); and wherein, at both ends of the columnar portion in a longitudinal direction, the first and the second component each have end portions, the end portions being either curved portions (31b, 31c, 32b, 32c) or second columnar portions (41b, 41c, 42b, 42c); and wherein the end portions are bent toward the same direction, characterized in that the first component (31, 32) and the second component (41, 42) are connected by connection members at both end portions in the longitudinal direction of the magnetic core (30, 40) which include holding portions that hold the end portions (31b, 31c, 41b. 41c) of the first component (31, 41) and engagement portions to be engaged with engagement protrusions (32d, 32e) of the second component (32, 42), wherein the engagement protrusions (32d, 32e) are respectively provided on a front surface and a rear surface of the second component (32, 42) on each of its end portions (32b, 32c, 42b, 42c). multi-phase electrical wires (21, 22, 23) configured to carry electric currents with different phases; and a magnetic core (30, 40) having a ring shape, around which the electrical wires (21, 22, 23) are wound, wherein the magnetic core (30, 40) has a division type in which a first component (31, 41) constituting a part of the ring shape, and a second component (32, 42) constituting a remaining part of the ring shape are connected, wherein the electrical wires (21, 22, 23) with all phases are only wound around the first component (31,41); wherein the first and second component (31, 32, 41, 42) each have a columnar portion (31a, 32a, 41a, 42a); and wherein, at both ends of the columnar portion in a longitudinal direction, the first and the second component each have end portions, the end portions being either curved portions (31b, 31c, 32b, 32c) or second columnar portions (41b, 41c, 42b, 42c); and wherein the end portions are bent toward the same direction, characterized in that the first component (31, 32) and the second component (41, 42) are connected by connection members at both end portions in the longitudinal direction of the magnetic core (30, 40) which include holding portions that hold the end portions (31b, 31c, 41b. 41c) of the first component (31, 41) and engagement portions to be engaged with engagement protrusions (32d, 32e) of the second component (32, 42), wherein the engagement protrusions (32d, 32e) are respectively provided on a front surface and a rear surface of the second component (32, 42) on each of its end portions (32b, 32c, 42b, 42c).