The invention provides UV-cured solder resist ink and a preparation method thereof. The UV-cured solder resist ink is UV-cured, has the solid content of 100%, does not emit any VOC during production and use, and is environment-friendly. Due to adoption of inkjet printing, the problem that the conventional UV solder resist ink cannot reach precision is solved, and the precision can reach 3mil. TheUV-cured solder resist ink comprises the following components in parts by weight: 60-90 parts of an acrylic monomer, 10-30 parts of barium sulfate, 0.1-2 parts of a pigment and 3-10 parts of a photoinitiator, wherein the acrylic monomer comprises a trifunctional acrylic monomer, a bifunctional acrylic monomer and a monofunctional acrylic monomer. The UV-cured solder resist ink has relatively goodsolder resistance and a relatively high curing speed.