A polyphenylene sulfide resin composition comprising (a) a polyphenylene sulfide resin and (b) an olefin-based resin, and satisfying the following conditions (i) to (vi): (i) the mixing ratio of the polyphenylene sulfide resin (a) and the olefin-based resin (b) is such that the amount of the polyphenylene sulfide resin (a) is in a range from 95 to 60 wt%, while the amount of the olefin-based resin (b) is in a range from 5 to 40 wt%, with the total weight of both the ingredients as 100 wt%; (ii) the polyphenylene sulfide resin comprises a polyphenylene sulfide resin (a-1) which has an ash content of 0.35 wt% to 0.65 wt%, a chloroform extractable fraction of 2 to 4 wt% and has a melt flow rate of 100 to 400 g/10 min as measured at a temperature of 315.5°C and at a load of 5000 g according to ASTM-D-1238 wherein the ask content and the chloroform extractable fraction are determined according to the methods described in the description; (iii) the olefin-based resin (b) comprises two copolymers: (b-1) an epoxy group-containing olefin copolymer and (b-2) an ethylene/α-olefin copolymer obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms; (iv) as the morphology of the polyphenylene sulfide resin composition observed by an electron microscope, the polyphenylene sulfide resin (a) forms a continuous phase, and the olefin-based resin (b) forms a dispersion phase and has a core-shell structure having the ethylene/α-olefin copolymer (b-2) acting as a core component contained in the epoxy group-containing olefin copolymer (b-1) acting as a shell component; (v) the melt flow rate of the polyphenylene sulfide resin composition measured at a temperature of 315.5°C and at a load of 5000 g according to ASTM-D-1238 is in a range from 10 to 50 g/10 min; and (vi) The notched impact strength of the polyphenylene sulfide resin composition measured at -40°C according to ASTM-D-256 is 300 J/m or more. (a) a polyphenylene sulfide resin and (b) an olefin-based resin, and satisfying the following conditions (i) to (vi): (i) the mixing ratio of the polyphenylene sulfide resin (a) and the olefin-based resin (b) is such that the amount of the polyphenylene sulfide resin (a) is in a range from 95 to 60 wt%, while the amount of the olefin-based resin (b) is in a range from 5 to 40 wt%, with the total weight of both the ingredients as 100 wt%; (ii) the polyphenylene sulfide resin comprises a polyphenylene sulfide resin (a-1) which has an ash content of 0.35 wt% to 0.65 wt%, a chloroform extractable fraction of 2 to 4 wt% and has a melt flow rate of 100 to 400 g/10 min as measured at a temperature of 315.5°C and at a load of 5000 g according to ASTM-D-1238 wherein the ask content and the chloroform extractable fraction are determined according to the methods described in the description; (iii) the olefin-based resin (b) comprises two copolymers: (b-1) an epoxy group-containing olefin copolymer and (b-2) an ethylene/α-olefin copolymer obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms; (iv) as the morphology of the polyphenylene sulfide resin composition observed by an electron microscope, the polyphenylene sulfide resin (a) forms a continuous phase, and the olefin-based resin (b) forms a dispersion phase and has a core-shell structure having the ethylene/α-olefin copolymer (b-2) acting as a core component contained in the epoxy group-containing olefin copolymer (b-1) acting as a shell component; (v) the melt flow rate of the polyphenylene sulfide resin composition measured at a temperature of 315.5°C and at a load of 5000 g according to ASTM-D-1238 is in a range from 10 to 50 g/10 min; and (vi) The notched impact strength of the polyphenylene sulfide resin composition measured at -40°C according to ASTM-D-256 is 300 J/m or more. (i) the mixing ratio of the polyphenylene sulfide resin (a) and the olefin-based resin (b) is such that the amount of the polyphenylene sulfide resin (a) is in a range from 95 to 60 wt%, while the amount of the olefin-based resin (b) is in a range from 5 to 40 wt%, with the total weight of both the ingredients as 100 wt%; (ii) the polyphenylene sulfide resin comprises a polyphenylene sulfide resin (a-1) which has an ash content of 0.35 wt% to 0.65 wt%, a chloroform extractable fraction of 2 to 4 wt% and has a melt flow rate of 100 to 400 g/10 min as measured at a temperature of 315.5°C and at a load of 5000 g according to ASTM-D-1238 wherein the ask content and the chloroform extractable fraction are determined according to the methods described in the description; (iii) the olefin-based resin (b) comprises two copolymers: (b-1) an epoxy group-containing olefin copolymer and (b-2) an ethylene/α-olefin copolymer obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms; (iv) as the morphology of the polyphenylene sulfide resin composition observed by an electron microscope, the polyphenylene sulfide resin (a) forms a continuous phase, and the olefin-based resin (b) forms a dispersion phase and has a core-shell structure having the ethylene/α-olefin copolymer (b-2) acting as a core component contained in the epoxy group-containing olefin copolymer (b-1) acting as a shell component; (v) the melt flow rate of the polyphenylene sulfide resin composition measured at a temperature of 315.5°C and at a load of 5000 g according to ASTM-D-1238 is in a range from 10 to 50 g/10 min; and (vi) The notched impact strength of the polyphenylene sulfide resin composition measured at -40°C according to ASTM-D-256 is 300 J/m or more.