The present disclosure relates to a catalyst used in the preparation of acrylic acid and acrylic acid preparation method using the same, and more specifically, discloses a catalyst capable of enhancing selectivity of acrylic acid and a production yield of acrylic acid when preparing acrylic acid from allyl alcohol using a heterogeneous catalyst including bimetallic alloy catalyst particles of gold and another metal, and an acrylic acid preparation method using the same.