An anti-corrosion structure for wire connecting portion, comprising: a wire including a core made of metal and covered with a coating; a terminal (10; 50) made of a metal different from the core and including a wire connecting portion (30; 52) connected to an end of the wire; a sealing resin (33; 53) sealing the wire connecting portion (30; 52) with resin; and a housing (40; 60) including a through hole in which the terminal (10; 50) is accommodated, wherein the wire connecting portion (30; 52) includes an exposed portion (34; 54), the exposed portion (34; 54) being obtained after the sealing resin (33; 53) is rubbed against an inner wall of the through hole, the exposed portion (34; 54) being positioned in an intermediate part of the wire connecting portion (30; 52) excluding a front end part and a rear end part thereof, wherein the wire connecting portion (30; 52) includes a wire barrel portion and an insulation barrel portion, the wire barrel portion being crimped onto the core, the insulation barrel portion including a barrel piece (32A; 52A) crimped onto the coating, and the exposed portion (34; 54) is arranged on an outer peripheral surface (32C; 52C) of the barrel piece (32A; 52A) located between a front end surface and a rear end surface of the barrel piece (32A; 52A), characterized in that the through hole includes a barrel accommodating portion in which the barrel piece (32A; 52A) is accommodated, the barrel accommodating portion being radially widened at a rear end opening side of the through hole to obtain an enlarged diameter portion, and a front end of the enlarged diameter portion is a step portion (44; 62) that is capable of coming into contact with the exposed portion (34; 54). a wire including a core made of metal and covered with a coating; a terminal (10; 50) made of a metal different from the core and including a wire connecting portion (30; 52) connected to an end of the wire; a sealing resin (33; 53) sealing the wire connecting portion (30; 52) with resin; and a housing (40; 60) including a through hole in which the terminal (10; 50) is accommodated, wherein the wire connecting portion (30; 52) includes an exposed portion (34; 54), the exposed portion (34; 54) being obtained after the sealing resin (33; 53) is rubbed against an inner wall of the through hole, the exposed portion (34; 54) being positioned in an intermediate part of the wire connecting portion (30; 52) excluding a front end part and a rear end part thereof, wherein the wire connecting portion (30; 52) includes a wire barrel portion and an insulation barrel portion, the wire barrel portion being crimped onto the core, the insulation barrel portion including a barrel piece (32A; 52A) crimped onto the coating, and the exposed portion (34; 54) is arranged on an outer peripheral surface (32C; 52C) of the barrel piece (32A; 52A) located between a front end surface and a rear end surface of the barrel piece (32A; 52A), characterized in that the through hole includes a barrel accommodating portion in which the barrel piece (32A; 52A) is accommodated, the barrel accommodating portion being radially widened at a rear end opening side of the through hole to obtain an enlarged diameter portion, and a front end of the enlarged diameter portion is a step portion (44; 62) that is capable of coming into contact with the exposed portion (34; 54).