Provided an ultraviolet-sensing sheet that facilitates measurement of ultraviolet irradiance over a wide area, that is suitable in ultraviolet irradiance in a range from 1 to 1,000 mJ/cm2, a method for manufacturing such an ultraviolet-sensing sheet, and a method for sensing ultraviolet. The ultraviolet-sensing sheet has a change in reflection density ΔD1 of 0.2 or more over a range of cumulative illuminance 1 mJ/cm2 or more and less than 10 mJ/cm2, a change in reflection density ΔD2 of 0.2 or more over a range of cumulative illuminance 10 mJ/cm2 or more and less than 100 mJ/cm2, and a change in reflection density ΔD3 of 0.2 or more over a range of cumulative illuminance 100 mJ/cm2 or more and 1,000 mJ/cm2 or less, as measured at a wavelength of 365 nm when the ultraviolet-sensing sheet is irradiated with a high-pressure mercury lamp.