Radically polymerizable composition, a cured product and a plastic lens

It has a low viscosity suitable for coating, and that shows the cured product of high refractive index, excellent toughness, comprising the radical polymerizable composition does not cause cracking or chipping during cutting, curing the composition cured product, and to provide a plastic lens formed by curing the composition. Radicals and phenyl benzyl (meth) acrylate (A), a urethane having an aromatic ring in the molecular structure (meth) acrylate (X), characterized in that it contains a radical polymerization initiator and (Y) as essential components polymerizable composition.