Provided is an additive masterbatch having excellent storage stability (agglomeration resistance), which also has reduced surface tackiness despite comprising a low-melting-point resin additive at a high concentration. The additive masterbatch of the present invention is characterized by comprising, with respect to 100 parts by mass of (A) a polyolefin resin, 65 to 300 parts by mass of (B) a resin additive having a melting point of not higher than 80° C.; and 0.8 to 24 parts by mass of (C) a benzotriazole-based ultraviolet absorber.