ADHESIVE COMPOSITION, ADHESIVE LAYER, AND ADHESIVE SHEET

PROBLEM TO BE SOLVED: To provide an adhesive composition that is capable of providing an adhesive layer in which titanium-based nanoparticles are stably dispersed, the adhesive layer having more enhanced mechanical properties, being excellent refractive index and being excellent adhesive force; and to provide an adhesive sheet or the like which uses the adhesive composition.SOLUTION: The adhesive composition is prepared so as to contain a (meth)acrylic polymer that contains, as a monomer component, 50 wt.% or more of a (meth)acrylate represented by CH=C(CR)COOR(wherein Rrepresents hydrogen or a methyl group; and Rrepresents a 1-20C unsubstituted or substituted alkyl group), has a weight-average molecular weight of 500,000-3,000,000 as determined by gel permeation chromatography, and does not substantially contain an acid component; an aromatic polymer that has a weight-average molecular weight of 200-900 as determined by gel permeation chromatography in an amount of 120-400 pts.wt. to 100 pts.wt. of the (meth)acrylic polymer; and titanium-based nanoparticles that have an average particle diameter of 5-100 nm in an amount of 150-600 pts.wt. to 100 pts.wt. of the (meth)acrylic polymer.