The object is providing a water-in-oil emulsion sunscreen cosmetic having a property not present in the prior art, in which UV protection ability improve upon contact with water, sweat and the like in comparison with that directly after application, and also having pleasant texture and easy to wash off. The present invention provides a water-in-oil emulsion sunscreen cosmetic comprising (A) 6 to 40 mass% of a UV protective agent; (B) an organic-modified clay mineral; (C) an oil-phase-thickening agent, other than (B) and (D) a silicone-based surfactant having an HLB of less than 8, wherein the ratio, [total quantity of component (B) and component (C)] / [total quantity of (E) non-volatile liquid oils except silicone oils], is 0.04 or more and less than 0.68.