A curable composition that gives a cured product exhibiting a high refractive index and a surface without defects such as roughness or cracks, a cured product of the composition, and a compound that may be blended to the composition. In a curable composition including a triazine compound having three aromatic-ring-containing groups each bonded to the triazine ring via an amino group, an aromatic-ring-containing group having a specific structure having a radically polymerizable group-containing group or a cationically polymerizable group-containing group is used as at least one of the three aromatic-ring-containing groups bonded to the triazine ring in the triazine compound mentioned above.