There are provided a composition for coating which can form an ink receiving layer having excellent adhesion with hydrophobic substrates, water-resistance and printing stability, and an optical recording medium having an ink receiving layer formed from this composition. The composition contains a radiation-curable compound (A) composed of 50 to 90% by weight of a monofunctional (meth) acrylic monomer and 10 to 50% by weight of a multifunctional (meth) acrylic monomer, a water-absorbing organic filler (C) in an amount of 10 to 60% by weight relative to (A), and a water-absorbing inorganic filler (D) in an amount of 1 to 20% by weight relative to (A). This composition is applied on a protecting film (6) and cured to form an ink receiving layer (7), to obtain an optical disk (1).