The present invention provides an adhesive composition which has a cured product exhibiting high transparency and a high refractive index, and which has high adhesive strength and experiences little reduction in the adhesive strength, even when exposed to high temperatures. In order to achieve the above the adhesive composition includes: (1) a hydrocarbon polymer having a total light transmittance of visible light, as measured according to JIS K7361-1, of at least 80%; (2) at least one kind of (meth)acrylic monomer selected from a mono(meth)acrylic monomer having one (meth)acrylic group in a molecule and a di(meth)acrylic monomer having two (meth)acrylic groups in a molecule; and (3) a photoinitiator; wherein 30-190 parts by weight of component (2) are included relative to 100 parts by weight of component (1).