A new granulation technology for producing spherical particles of a rubber antioxidant and its key factors were studied. The granulation is based on the interfacial tension and immiscibility of the rubber antioxidant in water. Melted antioxidant was ejected from nozzles to form drops in air that fell into a water tower where they were cooled and solidified into spherical particles as they fell. After dewatering and air drying, spherical particles with a uniform size were obtained. Experiments performed on the granulation of antioxidant 4020 are described and the key factors, including falling height, drop temperature and surfactant concentration in water were studied. The mechanism of drop entrancement in water was analyzed and the stable operating conditions were investigated. The technology produces spherical particles with a uniform size using smaller equipment and is also suitable for producing spherical particles from other melted materials with similar physical properties.