A paper-sheet recognition apparatus that acquires information from a paper sheet and recognizes the paper sheet based on the information, the paper-sheet recognition apparatus comprising: at least one light emitting unit (111, 121, 122) that includes one of the following: a first reflective light source and a second reflective light source; or a combination of the first reflective light source, the second reflective light source and a transmissive light source; wherein the at least one light emitting unit is configured to emit first to n-th lights, n being an integer equal to or larger than 2, of different wavelengths therefrom; an emission controller that performs emission control of the first to n-th lights emitted from the at least one light emitting unit (111, 121, 122); and a light receiving unit (113, 124) that receives a component of a light, which has been emitted from the at least one light emitting unit (111, 121, 122) and then reflected from or transmitted through the paper sheet; characterized in that the emission controller performs the emission control of the first to n-th lights such that, in one emission cycle, a number of light emissions of at least one of the first to n-th lights differs from a number of light emissions of other lights of the first to n-th lights depending on information desired to be used in the recognizing of the paper sheet, wherein the one emission cycle is a cycle of the emission control of the first to n-th lights according to an emission control program created beforehand. at least one light emitting unit (111, 121, 122) that includes one of the following: a first reflective light source and a second reflective light source; or a combination of the first reflective light source, the second reflective light source and a transmissive light source; wherein the at least one light emitting unit is configured to emit first to n-th lights, n being an integer equal to or larger than 2, of different wavelengths therefrom; an emission controller that performs emission control of the first to n-th lights emitted from the at least one light emitting unit (111, 121, 122); and a light receiving unit (113, 124) that receives a component of a light, which has been emitted from the at least one light emitting unit (111, 121, 122) and then reflected from or transmitted through the paper sheet; characterized in that the emission controller performs the emission control of the first to n-th lights such that, in one emission cycle, a number of light emissions of at least one of the first to n-th lights differs from a number of light emissions of other lights of the first to n-th lights depending on information desired to be used in the recognizing of the paper sheet, wherein the one emission cycle is a cycle of the emission control of the first to n-th lights according to an emission control program created beforehand. a first reflective light source and a second reflective light source; or a combination of the first reflective light source, the second reflective light source and a transmissive light source; wherein the at least one light emitting unit is configured to emit first to n-th lights, n being an integer equal to or larger than 2, of different wavelengths therefrom; an emission controller that performs emission control of the first to n-th lights emitted from the at least one light emitting unit (111, 121, 122); and a light receiving unit (113, 124) that receives a component of a light, which has been emitted from the at least one light emitting unit (111, 121, 122) and then reflected from or transmitted through the paper sheet; characterized in that the emission controller performs the emission control of the first to n-th lights such that, in one emission cycle, a number of light emissions of at least one of the first to n-th lights differs from a number of light emissions of other lights of the first to n-th lights depending on information desired to be used in the recognizing of the paper sheet, wherein the one emission cycle is a cycle of the emission control of the first to n-th lights according to an emission control program created beforehand.