A paper sheet handling apparatus for recognizing a paper sheet, comprising: a memory storing data for recognition to be used for recognizing the paper sheet; a recognition unit configured to recognize the paper sheet based on the data for recognition; an operation unit for performing an instruction operation relating to a paper sheet processing; and a control unit configured to perform the paper sheet processing based on the instruction operation performed by using the operation unit, wherein, in a usual processing, the recognition unit is configured to recognize the paper sheet based on the data for recognition in the memory and data acquired from the paper sheet, a data collection processing is performed after the instruction operation by a user through the operation unit, in the data collection processing, the recognition unit is configured to collect data from the paper sheet that has not been correctly recognized by the recognition unit in the usual processing, in the usual processing, the recognition unit acquires data only by a sensor necessary to recognize a processing target paper sheet and/or only from a part of the processing target paper sheet depending on a kind of the processing target paper sheet, and the acquired data is deleted after completion of a recognition process irrespective of whether a type of the processing target paper sheet is to be rejected or not to be rejected, and in the data collection processing, the recognition unit uses all the sensors and acquires data from the entire front surface and the entire back surface of the processing target paper sheet, and the acquired data is stored and retained in the memory wherein the control unit is configured to select the data to be stored in the memory depending on a selected type of the paper sheets. a memory storing data for recognition to be used for recognizing the paper sheet; a recognition unit configured to recognize the paper sheet based on the data for recognition; an operation unit for performing an instruction operation relating to a paper sheet processing; and a control unit configured to perform the paper sheet processing based on the instruction operation performed by using the operation unit, wherein, in a usual processing, the recognition unit is configured to recognize the paper sheet based on the data for recognition in the memory and data acquired from the paper sheet, a data collection processing is performed after the instruction operation by a user through the operation unit, in the data collection processing, the recognition unit is configured to collect data from the paper sheet that has not been correctly recognized by the recognition unit in the usual processing, in the usual processing, the recognition unit acquires data only by a sensor necessary to recognize a processing target paper sheet and/or only from a part of the processing target paper sheet depending on a kind of the processing target paper sheet, and the acquired data is deleted after completion of a recognition process irrespective of whether a type of the processing target paper sheet is to be rejected or not to be rejected, and in the data collection processing, the recognition unit uses all the sensors and acquires data from the entire front surface and the entire back surface of the processing target paper sheet, and the acquired data is stored and retained in the memory wherein the control unit is configured to select the data to be stored in the memory depending on a selected type of the paper sheets.