A planarized layer forming apparatus operable to use a pressing member to form a planarized layer of a curable composition on a substrate is provided. The apparatus comprises a pressing member holder for holding the pressing member, a substrate holder for holding the substrate, a curing device for curing the curable composition on the substrate, and a chamber for containing the pressing member holder and the substrate holder, and form a sealed space. The curable composition is caused to come into contact with the pressing member. After the contact, holding of the pressing member is released, and a space inside the chamber is pressurized. In a state where holding of the pressing member is released and the space inside the chamber is pressurized, the planarized layer is formed by curing the curable composition by the curing device.