NOVELTY - An adhesive composition comprises dinaphtho thiophene-type compound (I) having one or more polymerizable functional groups with ethylenically unsaturated double bond, as component (A), monofunctional (meth)acrylate having one or more aromatic rings as component (B), and a radical photopolymerization initiator as a component (C). The content of component (A) is 15-50 parts mass with respect to total amount of adhesive composition. The content of component (B) is 50-85 parts mass with respect to total amount of adhesive composition.    USE - Adhesive composition is used for optical components. Uses include but are not limited to liquid crystal panel, organic electroluminescent panel, touch panel, projector, smart phone, mobile telephone, digital camera, light-emitting diode, solar cell and lens used for lithium-ion battery.    ADVANTAGE - The adhesive composition provides optical components having high refractive index and transparency.    DETAILED DESCRIPTION - An adhesive composition comprises dinaphtho thiophene-type compound of formula (I) and having one or more polymerizable functional groups with ethylenically unsaturated double bond, as component (A), monofunctional (meth)acrylate having one or more aromatic rings as component (B), and a radical photopolymerization initiator as a component (C). The content of component (A) is 15-50 parts mass with respect to total amount of adhesive composition. The content of component (B) is 50-85 parts mass with respect to total amount of adhesive composition.    X=single bond, bivalent organic group chosen from alkylene, aralkylene, alkenylene optionally containing hetero atom including O, S or N, alkylene including ester bond, amide bond, imide bond bonded in principal chain, arylene, aralkylene, bivalent substituted aryl, bivalent substituted hetero aryl, or bivalent substituted silyl, or bivalent atom chosen from O, S, Sn or P having coupling with another atom;    R1=H or methyl;    c,d=0-4;    or c+d=1-4;    R=organic group, hydroxy, amino, nitro, thiol, sulfo, halo or silyl (optionally substituted);    a(R),b(R)=substituent bonded with substitutable carbon atoms in naphthalene ring;and    a,b=0-5.    when X is bivalent atom, X is coupled with any of substitutable carbon atom in naphthalene ring.