An ultraviolet curable resin composition includes (A) an ultraviolet curable resin, (B) an epoxy compound having at least two epoxy groups in one molecule, (C) a photopolymerization initiator and (D) a diluent. The ultraviolet curable resin (A) is obtained by the steps of polymerizing an ethylenically unsaturated monomer component containing (a) an ethylenically unsaturated monomer having epoxy group and (b) a compound having at least two ethylenically unsaturated groups in one molecule to prepare a copolymer, reacting the copolymer with (c) an ethylenically unsaturated monomer having carboxyl group to prepare a chemical intermediate, and reacting the chemical intermediate with (d) one of saturated and unsaturated polybasic acid anhydrides. This resin composition will be preferably used to prepare a photo solder resist ink developable with diluted alkaline aqueous solution.