The present invention provides an optically clear adhesive sheet with reduced delay bubble generation using a thermosetting polyurethane composition that has excellent flexibility and is capable of giving a thick film. The optically clear adhesive sheet of the present invention is an optically clear adhesive sheet formed of a cured product of a thermosetting polyurethane composition, the optically clear adhesive sheet having a shear storage modulus (G′) at 85° C. of 4.5×103 to 5.0×104 Pa, a loss tangent (tan δ) at 85° C. of 0.3 to 0.97, and a thickness of 50 to 2000 μm. The optically clear adhesive sheet preferably has an adhesive strength measured by a 180° peel test of 2 N/25 mm or more.