Sheet determination apparatus

In order to provide a sheet determination apparatus having a high reliability and capable of correctly determining the number and kinds of sheets even when sheets having a fold, breakage, tear, or the like are transported in an unfavorable state of overlapping transport, skew transport, or the like, there is provided a thickness sensor with a plurality of thickness detection elements arranged over an entire width of an identification transport passage along a widthwise direction of transport of the transport passage, on which sheets are to be transported, profile data of sheets are extracted from thickness data detected every thickness detection element, and the extracted profile data and profile basic data of sheets, which are stored in a storage unit to constitute standards, are compared with each other and judged to determine the number of sheets.