A head lamp for a vehicle, the head lamp arranged by housing LED substrates (40, 50), to which LED light sources (42, 52) are mounted, inside a lamp body that consists of a lens and a housing supporting the lens, comprising: a resistivity substrate that is arranged separately from the LED substrates (40, 50), and has a plurality of resistances and functions as a driving circuit that adjusts drive currents of the LED light sources (42, 52), wherein the resistivity substrate is disposed inside the lamp body, the LED substrates (40, 50) consist of a low beam-side LED substrate that supports the low beam-side LED light sources, and a high beam-side LED substrate that supports the high beam-side LED light sources, the low beam-side LED substrate and the high beam-side LED substrate are oriented to be parallel to each other and horizontally, and are offset-disposed in the vehicle body front-rear direction, characterized in that at a position between the rear end of the LED substrate being positioned at the vehicle body front side and the rear end of the LED substrate being positioned at the vehicle body rear side, the resistivity substrate is disposed so as to be oriented vertically, and the head lamp further comprises: a reflector that reflects irradiation light from the LED light sources (42, 52) toward the vehicle body front side, wherein the resistivity substrate is disposed on the back surface side of the reflector; a partition wall orientated horizontally is provided between the resistivity substrate and the low beam-side LED substrate that is disposed above the resistivity substrate, and the partition wall extends toward the vehicle body front side to a position that is close to the back surface side of the reflector and overlaps with the rear end of the high beam-side LED substrate on the vehicle body front side, and above a notched portion, formed by notching a portion of the partition wall, a breathing hole that makes communication between the inside and the outside of the lamp body is provided, and a drive current supplied from the resistivity substrate is supplied to the high beam-side LED substrate by a first harness, and then supplied to the low beam-side LED substrate by a second harness, the notched portion is provided as a passage of the second harness. a resistivity substrate that is arranged separately from the LED substrates (40, 50), and has a plurality of resistances and functions as a driving circuit that adjusts drive currents of the LED light sources (42, 52), wherein the resistivity substrate is disposed inside the lamp body, the LED substrates (40, 50) consist of a low beam-side LED substrate that supports the low beam-side LED light sources, and a high beam-side LED substrate that supports the high beam-side LED light sources, the low beam-side LED substrate and the high beam-side LED substrate are oriented to be parallel to each other and horizontally, and are offset-disposed in the vehicle body front-rear direction, characterized in that at a position between the rear end of the LED substrate being positioned at the vehicle body front side and the rear end of the LED substrate being positioned at the vehicle body rear side, the resistivity substrate is disposed so as to be oriented vertically, and the head lamp further comprises: a reflector that reflects irradiation light from the LED light sources (42, 52) toward the vehicle body front side, wherein the resistivity substrate is disposed on the back surface side of the reflector; a partition wall orientated horizontally is provided between the resistivity substrate and the low beam-side LED substrate that is disposed above the resistivity substrate, and the partition wall extends toward the vehicle body front side to a position that is close to the back surface side of the reflector and overlaps with the rear end of the high beam-side LED substrate on the vehicle body front side, and above a notched portion, formed by notching a portion of the partition wall, a breathing hole that makes communication between the inside and the outside of the lamp body is provided, and a drive current supplied from the resistivity substrate is supplied to the high beam-side LED substrate by a first harness, and then supplied to the low beam-side LED substrate by a second harness, the notched portion is provided as a passage of the second harness. a reflector that reflects irradiation light from the LED light sources (42, 52) toward the vehicle body front side, wherein the resistivity substrate is disposed on the back surface side of the reflector; a partition wall orientated horizontally is provided between the resistivity substrate and the low beam-side LED substrate that is disposed above the resistivity substrate, and the partition wall extends toward the vehicle body front side to a position that is close to the back surface side of the reflector and overlaps with the rear end of the high beam-side LED substrate on the vehicle body front side, and above a notched portion, formed by notching a portion of the partition wall, a breathing hole that makes communication between the inside and the outside of the lamp body is provided, and a drive current supplied from the resistivity substrate is supplied to the high beam-side LED substrate by a first harness, and then supplied to the low beam-side LED substrate by a second harness, the notched portion is provided as a passage of the second harness.