A polypropylene-based resin composition comprising 100 parts by weight of the following component, 18 parts by weight or more and 65 parts by weight or less of the following component, 6 parts by weight or more and 45 parts by weight or less of the following component, 25 parts by weight or more and 60 parts by weight or less of the following component, 0.1 part by weight or more and 6.5 parts by weight or less of the following component and 0.15 part by weight or more and 5.0 parts or less by weight of the following component: a propylene-ethylene block copolymer A satisfying the following to: the amount of a room temperature decane-soluble part is 8 wt% or more and 35 wt% or less; the room temperature decane-soluble part has a limiting viscosity [η] of 1.0 dl/g or more and 10.0 dl/g or less; the amount of ethylene in the room temperature decane-soluble part is 33 mol% or more and 48 mol% or less; the melt flow rate (MFR: 230°C, under the load of 2.16 kg) is 20g/10 min or more and 100g/10 min or less; A propylene-ethylene block copolymer B satisfying the following to: the amount of a room temperature decane-soluble part is 16 wt% or more and 35 wt% or less; the room temperature decane-soluble part has a limiting viscosity [η] of 5.0 dl/g or more and 10.0 dl/g or less; the amount of ethylene in the room temperature decane-soluble part is 36 mol% or more and 49 mol% or less; the melt flow rate (MFR: 230°C, under the load of 2.16 kg) is 1g/10 min or more and less than 20g/10 min; an ethylene-α-olefin copolymer having a melt flow rate (230°C, under the load of 2.16 kg) of 0.5g/10 min or more and 20g/10 min or less; an inorganic filler having an average particle diameter of 1 μm or more and 14 μm or less; an acid-modified polypropylene; and a lubricant a propylene-ethylene block copolymer A satisfying the following to: the amount of a room temperature decane-soluble part is 8 wt% or more and 35 wt% or less; the room temperature decane-soluble part has a limiting viscosity [η] of 1.0 dl/g or more and 10.0 dl/g or less; the amount of ethylene in the room temperature decane-soluble part is 33 mol% or more and 48 mol% or less; the melt flow rate (MFR: 230°C, under the load of 2.16 kg) is 20g/10 min or more and 100g/10 min or less; the amount of a room temperature decane-soluble part is 8 wt% or more and 35 wt% or less; the room temperature decane-soluble part has a limiting viscosity [η] of 1.0 dl/g or more and 10.0 dl/g or less; the amount of ethylene in the room temperature decane-soluble part is 33 mol% or more and 48 mol% or less; the melt flow rate (MFR: 230°C, under the load of 2.16 kg) is 20g/10 min or more and 100g/10 min or less; A propylene-ethylene block copolymer B satisfying the following to: the amount of a room temperature decane-soluble part is 16 wt% or more and 35 wt% or less; the room temperature decane-soluble part has a limiting viscosity [η] of 5.0 dl/g or more and 10.0 dl/g or less; the amount of ethylene in the room temperature decane-soluble part is 36 mol% or more and 49 mol% or less; the melt flow rate (MFR: 230°C, under the load of 2.16 kg) is 1g/10 min or more and less than 20g/10 min; the amount of a room temperature decane-soluble part is 16 wt% or more and 35 wt% or less; the room temperature decane-soluble part has a limiting viscosity [η] of 5.0 dl/g or more and 10.0 dl/g or less; the amount of ethylene in the room temperature decane-soluble part is 36 mol% or more and 49 mol% or less; the melt flow rate (MFR: 230°C, under the load of 2.16 kg) is 1g/10 min or more and less than 20g/10 min; an ethylene-α-olefin copolymer having a melt flow rate (230°C, under the load of 2.16 kg) of 0.5g/10 min or more and 20g/10 min or less; an inorganic filler having an average particle diameter of 1 μm or more and 14 μm or less; an acid-modified polypropylene; and a lubricant