A curable composition which provides a coating layer having high adhesion to a substrate and a hard coat layer and extremely excellent photochromic properties such as high color development intensity, high fading speed and excellent durability. This composition comprises (1) 100 parts by weight of radically polymerizable monomers including a silyl monomer such as γ-methacryloyloxypropyl trimethoxysilane and/or an isocyanate monomer such as 2-isocyanatoethoxy methacrylate, (2) 0.01 to 20 parts by weight of an amine compound and (3) 0.01 to 20 parts by weight of a photochromic compound. A photochromic optical material having excellent adhesion between a photochromic coating layer and a resin substrate and obtained by using this composition as a coating material and a process for producing the photochromic optical material.