A wire rod consisting of: in mass percent, hereinafter the same for chemical composition; C in a content of 0.8% to 1.2%, Si in a content of 0.1% to 2.0%; Mn in a content of 0.1% to 2.0%; N in a content of 0.002% to 0.010%; Al in a content of 0.04% to 0.15%; P in a content of 0.02% or less; and S in a content of 0.02% or less; and optionally at least one element selected from the group consisting of: Cr in a content of 1.0% or less, excluding 0%; Ni in a content of 1.0% or less, excluding 0%; Co in a content of 1.0% or less, excluding 0%; Mo in a content of 1.0% or less, excluding 0%; and Cu in a content of 0.5% or less, excluding 0%; and optionally at least one element selected from the group consisting of: B in a content of 0.005% or less, excluding 0%; Nb in a content of 0.5% or less, excluding 0%; and V in a content of 0.5% or less, excluding 0%; with the remainder being iron and inevitable impurities; the Al content and N content meeting a condition specified by Expression given as follows: Al ≤ − 2.1 × 10 × N + 0.255 where [Al] and are contents in mass percent of Al and N, respectively; the wire rod having a microstructure comprising 95 percent by area or more of a pearlite; the wire rod having a content of AIN of 0.005% or more; and a percentage of AlN particles having a diameter d GM of 10 to 20 μm being 50% or more in number percent in an extreme value distribution of maximum values of the diameters d GM of AIN particles, where the diameter d GM is represented by a geometrical mean (ab) 1/2 of a length "a" and a thickness "b" of an AlN particle, wherein the term "length "a"" of an AIN particle refers to the length (dimension) of the AlN particle in the wire rod longitudinal direction; the term "thickness "b"" of the AlN particle refers to a dimension of the AlN particle in a direction perpendicular to the wire rod longitudinal direction, and the size of an AIN particle having the maximum size in an observation view field in the cross section is measured according to JIS G0555, wherein the measurement is performed in arbitrary twenty view fields and wherein Group D and Group DS inclusions as specified in JIS G0551 are regarded as AlN particles in the measurement. C in a content of 0.8% to 1.2%, Si in a content of 0.1% to 2.0%; Mn in a content of 0.1% to 2.0%; N in a content of 0.002% to 0.010%; Al in a content of 0.04% to 0.15%; P in a content of 0.02% or less; and S in a content of 0.02% or less; and optionally at least one element selected from the group consisting of: Cr in a content of 1.0% or less, excluding 0%; Ni in a content of 1.0% or less, excluding 0%; Co in a content of 1.0% or less, excluding 0%; Mo in a content of 1.0% or less, excluding 0%; and Cu in a content of 0.5% or less, excluding 0%; Cr in a content of 1.0% or less, excluding 0%; Ni in a content of 1.0% or less, excluding 0%; Co in a content of 1.0% or less, excluding 0%; Mo in a content of 1.0% or less, excluding 0%; and Cu in a content of 0.5% or less, excluding 0%; and optionally at least one element selected from the group consisting of: B in a content of 0.005% or less, excluding 0%; Nb in a content of 0.5% or less, excluding 0%; and V in a content of 0.5% or less, excluding 0%; B in a content of 0.005% or less, excluding 0%; Nb in a content of 0.5% or less, excluding 0%; and V in a content of 0.5% or less, excluding 0%; with the remainder being iron and inevitable impurities; the Al content and N content meeting a condition specified by Expression given as follows: Al ≤ − 2.1 × 10 × N + 0.255 where [Al] and are contents in mass percent of Al and N, respectively; the wire rod having a microstructure comprising 95 percent by area or more of a pearlite; the wire rod having a content of AIN of 0.005% or more; and a percentage of AlN particles having a diameter d GM of 10 to 20 μm being 50% or more in number percent in an extreme value distribution of maximum values of the diameters d GM of AIN particles, where the diameter d GM is represented by a geometrical mean (ab) 1/2 of a length "a" and a thickness "b" of an AlN particle, wherein the term "length "a"" of an AIN particle refers to the length (dimension) of the AlN particle in the wire rod longitudinal direction; the term "thickness "b"" of the AlN particle refers to a dimension of the AlN particle in a direction perpendicular to the wire rod longitudinal direction, and the size of an AIN particle having the maximum size in an observation view field in the cross section is measured according to JIS G0555, wherein the measurement is performed in arbitrary twenty view fields and wherein Group D and Group DS inclusions as specified in JIS G0551 are regarded as AlN particles in the measurement.