An acrylic adhesive composition including an acrylic copolymer formed by polymerizing a monomer mixture is provided. The monomer mixture includes a monomer represented by [Formula 1], a (meth)acrylic monomer having a crosslinkable functional group, and an alkyl (meth)acrylate-based monomer. The acrylic copolymer has a branched polymer structure. The acrylic composition also includes a polyfunctional acrylate having two or more radically polymerizable functional groups, a first photoinitiator, and a second photoinitiator, wherein the first photoinitiator is an acetophenone-based photoinitiator, and the second photoinitiator is a phosphine oxide-based photoinitiator.