A vehicle-use alternating current generator regulator (19, 19a, 19b), comprising: an IC regulator (200, 201) wherein an IC chip that configures a voltage control circuit of the vehicle-use alternating current generator is sealed with resin, and a plurality of lead terminals for external connection protrudes from the sealing resin; and a regulator holder (100, 100a) having an IC regulator mounting portion, in which the IC regulator (200, 201) is mounted, and a lead opposing portion, provided on a periphery of the IC regulator mounting portion, and opposing the lead terminals, wherein at least one of the lead terminals has a lead protruding portion protruding towards the lead opposing portion from a contact joining the at least one of the lead terminals to an insert terminal of the regulator holder (100, 100a), and the IC regulator (200, 201) is positioned by the lead protruding portion being fitted into the lead opposing portion of the regulator holder (100, 100a), wherein the plurality of the lead terminals extend linearly from the sealing resin and are disposed in parallel with respect to the IC regulator (200, 201), and the said at least one lead terminal of the plurality of lead terminals to be positioned in the lead opposing portion is formed to be longer than the other lead terminals by an amount equivalent to the lead protruding portion, wherein a depressed portion (130, 131), in which the lead protruding portion of the at least one lead terminal is inserted, is provided in the lead opposing portion of the regulator holder (100, 100a), and wherein the depressed portion (130, 131) is lateral to a portion in which the lead protruding portion interferes with the lead opposing portion when mounting the IC regulator (200, 201) in the regulator holder, the depressed portion being either formed in a groove form towards a lateral edge of the lead opposing portion, wherein an inclined face portion that forms an insertion guide of the at least one lead terminal is provided on an inner face portion of the depressed portion; or being removed from an end of the lead opposing portion facing the IC regulator (200, 201), the depressed portion forming a lateral hole of the lead opposing portion, the lateral hole being opened in a direction in which the at least one lead terminal extends. an IC regulator (200, 201) wherein an IC chip that configures a voltage control circuit of the vehicle-use alternating current generator is sealed with resin, and a plurality of lead terminals for external connection protrudes from the sealing resin; and a regulator holder (100, 100a) having an IC regulator mounting portion, in which the IC regulator (200, 201) is mounted, and a lead opposing portion, provided on a periphery of the IC regulator mounting portion, and opposing the lead terminals, wherein at least one of the lead terminals has a lead protruding portion protruding towards the lead opposing portion from a contact joining the at least one of the lead terminals to an insert terminal of the regulator holder (100, 100a), and the IC regulator (200, 201) is positioned by the lead protruding portion being fitted into the lead opposing portion of the regulator holder (100, 100a), wherein the plurality of the lead terminals extend linearly from the sealing resin and are disposed in parallel with respect to the IC regulator (200, 201), and the said at least one lead terminal of the plurality of lead terminals to be positioned in the lead opposing portion is formed to be longer than the other lead terminals by an amount equivalent to the lead protruding portion, wherein a depressed portion (130, 131), in which the lead protruding portion of the at least one lead terminal is inserted, is provided in the lead opposing portion of the regulator holder (100, 100a), and wherein the depressed portion (130, 131) is lateral to a portion in which the lead protruding portion interferes with the lead opposing portion when mounting the IC regulator (200, 201) in the regulator holder, the depressed portion being either formed in a groove form towards a lateral edge of the lead opposing portion, wherein an inclined face portion that forms an insertion guide of the at least one lead terminal is provided on an inner face portion of the depressed portion; or being removed from an end of the lead opposing portion facing the IC regulator (200, 201), the depressed portion forming a lateral hole of the lead opposing portion, the lateral hole being opened in a direction in which the at least one lead terminal extends.