A solar cell includes a substrate of a first conductive type, an emitter layer which is positioned at one surface of the substrate and has a second conductive type opposite the first conductive type, an anti-reflection layer which is positioned on the emitter layer and has a contact line, and an electrode part positioned on the emitter layer exposed by the contact line. The electrode part includes a seed layer directly contacting the emitter layer. The emitter layer has a first thickness of a formation area of the anti-reflection layer and a second thickness of a formation area of the seed layer. The first thickness is different from the second thickness.