The present invention provides a polyacetal resin composition comprising a polyacetal resin (A) and a polyethylene resin (B), the blending ratio of the polyacetal resin (A) accounting for the total mass of the polyacetal resin (A) and the polyethylene resin (B) being 10 to 90 mass%, the melt flow rate of the polyacetal resin (A) measured under conditions of 190 DEG C and a 2.16-kg load being 30 g/10 min or lower, the polyethylene resin (B) being constituted of a modified polyethylene resin, the modification rate if the total mass of the polyethylene resin is 100 mass% being 0.01 mass% or higher, and the melt flow rate of the polyethylene resin (B) measured under conditions of 190 DEG C and a 2.16-kg load being 2.5 g/10 min or lower.