Application of low-energy electron beam to nonsolvent-type pressure-sensitive adhesive is investigated. Adhesive properties such as peel strength, dead load strength, and ball tack were closely related to the reaction behavior (gel fraction and graft efficiency) of the acrylate polymer-monomer system. The reaction behavior is eluciadated by combining the measurements of gel fraction, infrared spectrum of gel, and molecular weight distribution detected by gel permeation chromatogrophy. It was found that the adhesive property of electro beamcured adhesives depends on the molecular weight of added polymer, monomer concentration, and irradiation dose. Graft polymerization and moderate crosslinking by electron beam irradiation especially contribute to superior high adhesive properties.