A foaming resin composition of the present invention contains an aromatic vinyl-based resin and zinc oxide, wherein the size ratio (B/A), in which peak A is a 370 nm to 390 nm region and peak B is a 450 nm to 600 nm region, of zinc oxide is approximately 0.01 to approximately 1 when photoluminescence is measured, and the BET surface area thereof is approximately 1 m2/g to approximately 10 m2/g.