A method for preparing an article having an uneven microstructure on a surface thereof, including coating a surface of a mold having an uneven microstructure formed from an anodized alumina oxide on a surface with a release treatment solution including a mold release agent that includes one or more kinds of phosphoric ester compound and the pH of the aqueous solution when extracted with 50 mL of water with respect to 1 g of the mold release agent is 3.0 or more; andinterposing an active energy ray curable resin composition including a polymerizable compound, a polymerization initiator, and an internal release agent between the mold and the substrate, and curing the active energy ray curable resin composition by the irradiation with active energy rays to form a cured resin layer having the uneven microstructure transferred on a surface of the substrate.