The invention provides an
adhesive composition, an
adhesive and an
adhesive sheet which are suitable for optical components, such as polarization light panel, etc., and have light diffusivity, good
stress relaxation rate, uneveness follow-up property and durability. The composition contains first (methyl) acrylic ester polymers (A) having a Mw of 500-3000 thousands, second (methyl) acrylic ester polymers (B) having a Mw of 80000-300 thousands, a cross-linking agent (C) and light
diffusion micro-particles(D). The ratio of the polymers (B) with respect to 100 parts by
mass of the polymers (A) is 5 to 50 parts by
mass. The polymers (B) contain monomers having functional groups (b1) reacting with the cross-linking agent (C), and the ratio of the monomers in the polymers (B) is more than 1
mass% and less than 50 mass%. The polymers (A) do not contain monomers having functional groups reacting with the cross-linking agent (C) or contain monomers having functional groups (a1) having reactiveness with the cross-linking agent (C) lower than that of the functional groups (b1). The ratio of the light
diffusion micro-particles(D) with respect to 100 parts by mass of the polymers (A) and the polymers (B) is 5.0 to 50.0 parts by mass.