An adhesive composition of the present invention includes, as a main component, a polymer produced by copolymerization of a monomer composition including: styrene; a (meth)acrylic acid alkyl ester having a chain structure; a (meth)acrylic acid ester having an aliphatic ring; and a (meth)acrylic acid ester having an aromatic ring, wherein: the styrene is contained in a range of 40 to 69 parts by mass; the (meth)acrylic acid alkyl ester having the chain structure is contained in a range of 20 to 30 parts by mass; the (meth)acrylic acid ester having the aliphatic ring is contained in a range of 10 to 25 parts by mass; and the (meth)acrylic acid ester having the aromatic ring is contained in a range of 1 to 5 parts by mass, where the total amount of the above components is 100 parts by mass. This allows for provision of an adhesive composition having high adhesive strength under high-temperature environment, as well as high heat resistance, high alkali resistance, and easiness in stripping from semiconductor wafers and the like even after high-temperature processing.